Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability

cve CVE-2025-39682 3 sources, 3 claims · Watch

CISA Known Exploited Vulnerabilities writes:
Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version. Apply mitigations… the claim

What it is to other things

affectsdebian/debian_linux
NVD
affectslinux/linux_kernel
NVD
affectssiemens/simatic_cn_4100
NVD
affectssiemens/simatic_cn_4100_firmware
NVD
made_bydebian
NVD
made_bylinux
NVD
made_bysiemens
NVD

In words only, so not counted until a person confirms one:

affectslinux/linux
NVD says “Linux · Linux”

What each source says

PropertySourceSaidMeans here
Cvss
cvss
conflict
NVD9.8
receipt
Source
NVD
Its words
9.8
Read by
field:cve.metrics.cvssMetricV31[].cvssData.baseScore
Said since
2026-09-29 09:45 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2902c3ebcca52ca845c03182000e8d71d3a5196f",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "3439c15ae91a517cf3c650ea15a8987699416ad9",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "62708b9452f8eb77513115b17c4f8d1a22ebf843",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "6.0"
              },
              {
                "lessThan": "6.0",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.149",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.103",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.44",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.16.*",
                "status": "unaffected",
                "version": "6.16.4",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "6.17",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      },
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC CN 4100",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "V5.0",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
      }
    ],
    "cisaActionDue": "2026-09-21",
    "cisaExploitAdd": "2026-09-18",
    "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
    "cisaVulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability",
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "DE30211F-1A6B-457E-B19D-D3E385550199",
                "versionEndExcluding": "6.1.149",
                "versionStartIncluding": "6.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "F2293654-7169-49B5-8D0D-EE51EF8B8E48",
                "versionEndExcluding": "6.6.103",
                "versionStartIncluding": "6.2",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "12351F24-1133-4775-960C-F2B47E81298B",
                "versionEndExcluding": "6.12.44",
                "versionStartIncluding": "6.7",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AFC28995-B8C3-4B68-8CB6-78E792B6629D",
                "versionEndExcluding": "6.16.4",
                "versionStartIncluding": "6.13",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
                "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
                "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
                "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AA9D4F6E-9336-4026-B485-4227C861B356",
                "versionEndExcluding": "5.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          },
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*",
                "matchCriteriaId": "92619F5F-3679-4424-9455-3285FF1EF2F1",
                "vulnerable": false
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ],
        "operator": "AND"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntls: fix handling of zero-length records on the rx_list\n\nEach recvmsg() call must process either\n - only contiguous DATA records (any number of them)\n - one non-DATA record\n\nIf the next record has different type than what has already been\nprocessed we break out of the main processing loop. If the record\nhas already been decrypted (which may be the case for TLS 1.3 where\nwe don't know type until decryption) we queue the pending record\nto the rx_list. Next recvmsg() will pick it up from there.\n\nQueuing the skb to rx_list after zero-copy decrypt is not possible,\nsince in that case we decrypted directly to the user space buffer,\nand we don't have an skb to queue (darg.skb points to the ciphertext\nskb for access to metadata like length).\n\nOnly data records are allowed zero-copy, and we break the processing\nloop after each non-data record. So we should never zero-copy and\nthen find out that the record type has changed. The corner case\nwe missed is when the initial record comes from rx_list, and it's\nzero length."
      }
    ],
    "id": "CVE-2025-39682",
    "lastModified": "2026-09-21T12:00:36.613",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        },
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2025-39682",
            "options": [
              {
                "exploitation": "active"
              },
              {
                "automatable": "yes"
              },
              {
                "technicalImpact": "total"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-18T00:00:00+00:00",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2025-09-05T18:15:44.670",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677"
      },
      {
        "source": "af854a3a-2127-422b-91ae-364da2661108",
        "tags": [
          "Mailing List",
          "Third Party Advisory"
        ],
        "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
      },
      {
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
        "tags": [
          "Third Party Advisory"
        ],
        "url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html"
      },
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "tags": [
          "US Government Resource"
        ],
        "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39682"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Analyzed",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "NVD-CWE-Other"
          }
        ],
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-754"
          }
        ],
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ]
  }
}
—
Cvss
cvss
conflict
Red Hat7
receipt
Source
Red Hat
Its words
7.0
Read by
field:cvss3_score
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2025-39682",
  "CWE": null,
  "advisories": [
    "RHSA-2025:19223",
    "RHSA-2025:19224",
    "RHSA-2025:16880",
    "RHSA-2025:19104",
    "RHSA-2025:16904"
  ],
  "affected_packages": [
    "kernel-0:6.12.0-55.37.1.el10_0",
    "kernel-0:5.14.0-570.49.1.el9_6",
    "kernel-0:5.14.0-284.144.1.el9_2",
    "kernel-rt-0:5.14.0-284.144.1.rt14.429.el9_2",
    "kernel-0:5.14.0-427.96.1.el9_4"
  ],
  "bugzilla": "2393511",
  "bugzilla_description": "kernel: tls: fix handling of zero-length records on the rx_list",
  "cvss3_score": "7.0",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2025-09-05T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2025-39682.json",
  "severity": "moderate"
}
—
Cwes
cwes
CISA Known Exploited VulnerabilitiesCWE-754
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
CWE-754
Read by
field:cwes
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—
Due date
due_date
CISA Known Exploited Vulnerabilities2026-09-21
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
2026-09-21
Read by
field:dueDate
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—
Exploited
exploited
CISA Known Exploited Vulnerabilitiesyes
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
yes
Read by
const:yes
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—
Forensic triage
forensic_triage
CISA Known Exploited Vulnerabilitiestrue
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
Yes
Read by
field:forensicTriage
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—
Known ransomware campaign use
known_ransomware_campaign_use
CISA Known Exploited VulnerabilitiesUnknown
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
Unknown
Read by
field:knownRansomwareCampaignUse
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—
Packages
packages
Red Hatkernel-0:6.12.0-55.37.1.el10_0, kernel-0:5.14.0-570.49.1.el9_6, kernel-0:5.14.0-284.144.1.el9_2, kernel-rt-0:5.14.0-284.144.1.rt14.429.el9_2, kernel-0:5.14.0-427.96.1.el9_4
receipt
Source
Red Hat
Its words
kernel-0:6.12.0-55.37.1.el10_0, kernel-0:5.14.0-570.49.1.el9_6, kernel-0:5.14.0-284.144.1.el9_2, kernel-rt-0:5.14.0-284.144.1.rt14.429.el9_2, kernel-0:5.14.0-427.96.1.el9_4
Read by
field:affected_packages[]
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2025-39682",
  "CWE": null,
  "advisories": [
    "RHSA-2025:19223",
    "RHSA-2025:19224",
    "RHSA-2025:16880",
    "RHSA-2025:19104",
    "RHSA-2025:16904"
  ],
  "affected_packages": [
    "kernel-0:6.12.0-55.37.1.el10_0",
    "kernel-0:5.14.0-570.49.1.el9_6",
    "kernel-0:5.14.0-284.144.1.el9_2",
    "kernel-rt-0:5.14.0-284.144.1.rt14.429.el9_2",
    "kernel-0:5.14.0-427.96.1.el9_4"
  ],
  "bugzilla": "2393511",
  "bugzilla_description": "kernel: tls: fix handling of zero-length records on the rx_list",
  "cvss3_score": "7.0",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2025-09-05T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2025-39682.json",
  "severity": "moderate"
}
—
Product
product
not compared
CISA Known Exploited VulnerabilitiesKernel
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
Kernel
Read by
field:product
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—
Product
product
not compared
NVDLinux
receipt
Source
NVD
Its words
Linux
Read by
field:cve.affected[].affectedData[].product
Said since
2026-09-29 17:49 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
2026-09-29 17:49 UTCLinux
2026-09-29 09:45 UTC—
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2902c3ebcca52ca845c03182000e8d71d3a5196f",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "3439c15ae91a517cf3c650ea15a8987699416ad9",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "62708b9452f8eb77513115b17c4f8d1a22ebf843",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "6.0"
              },
              {
                "lessThan": "6.0",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.149",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.103",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.44",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.16.*",
                "status": "unaffected",
                "version": "6.16.4",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "6.17",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      },
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC CN 4100",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "V5.0",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
      }
    ],
    "cisaActionDue": "2026-09-21",
    "cisaExploitAdd": "2026-09-18",
    "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
    "cisaVulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability",
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "DE30211F-1A6B-457E-B19D-D3E385550199",
                "versionEndExcluding": "6.1.149",
                "versionStartIncluding": "6.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "F2293654-7169-49B5-8D0D-EE51EF8B8E48",
                "versionEndExcluding": "6.6.103",
                "versionStartIncluding": "6.2",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "12351F24-1133-4775-960C-F2B47E81298B",
                "versionEndExcluding": "6.12.44",
                "versionStartIncluding": "6.7",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AFC28995-B8C3-4B68-8CB6-78E792B6629D",
                "versionEndExcluding": "6.16.4",
                "versionStartIncluding": "6.13",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
                "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
                "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
                "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AA9D4F6E-9336-4026-B485-4227C861B356",
                "versionEndExcluding": "5.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          },
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*",
                "matchCriteriaId": "92619F5F-3679-4424-9455-3285FF1EF2F1",
                "vulnerable": false
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ],
        "operator": "AND"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntls: fix handling of zero-length records on the rx_list\n\nEach recvmsg() call must process either\n - only contiguous DATA records (any number of them)\n - one non-DATA record\n\nIf the next record has different type than what has already been\nprocessed we break out of the main processing loop. If the record\nhas already been decrypted (which may be the case for TLS 1.3 where\nwe don't know type until decryption) we queue the pending record\nto the rx_list. Next recvmsg() will pick it up from there.\n\nQueuing the skb to rx_list after zero-copy decrypt is not possible,\nsince in that case we decrypted directly to the user space buffer,\nand we don't have an skb to queue (darg.skb points to the ciphertext\nskb for access to metadata like length).\n\nOnly data records are allowed zero-copy, and we break the processing\nloop after each non-data record. So we should never zero-copy and\nthen find out that the record type has changed. The corner case\nwe missed is when the initial record comes from rx_list, and it's\nzero length."
      }
    ],
    "id": "CVE-2025-39682",
    "lastModified": "2026-09-21T12:00:36.613",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        },
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2025-39682",
            "options": [
              {
                "exploitation": "active"
              },
              {
                "automatable": "yes"
              },
              {
                "technicalImpact": "total"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-18T00:00:00+00:00",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2025-09-05T18:15:44.670",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677"
      },
      {
        "source": "af854a3a-2127-422b-91ae-364da2661108",
        "tags": [
          "Mailing List",
          "Third Party Advisory"
        ],
        "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
      },
      {
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
        "tags": [
          "Third Party Advisory"
        ],
        "url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html"
      },
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "tags": [
          "US Government Resource"
        ],
        "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39682"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Analyzed",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "NVD-CWE-Other"
          }
        ],
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-754"
          }
        ],
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ]
  }
}
—
Severity
severity
Red Hatmoderate
A flaw that is harder to exploit, or whose impact is limited.
receipt
Source
Red Hat
Its words
moderate
Read by
field:severity
Said since
2026-09-29 09:44 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
{
  "CVE": "CVE-2025-39682",
  "CWE": null,
  "advisories": [
    "RHSA-2025:19223",
    "RHSA-2025:19224",
    "RHSA-2025:16880",
    "RHSA-2025:19104",
    "RHSA-2025:16904"
  ],
  "affected_packages": [
    "kernel-0:6.12.0-55.37.1.el10_0",
    "kernel-0:5.14.0-570.49.1.el9_6",
    "kernel-0:5.14.0-284.144.1.el9_2",
    "kernel-rt-0:5.14.0-284.144.1.rt14.429.el9_2",
    "kernel-0:5.14.0-427.96.1.el9_4"
  ],
  "bugzilla": "2393511",
  "bugzilla_description": "kernel: tls: fix handling of zero-length records on the rx_list",
  "cvss3_score": "7.0",
  "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2025-09-05T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2025-39682.json",
  "severity": "moderate"
}
medium
Status
status
NVDAnalyzed
receipt
Source
NVD
Its words
Analyzed
Read by
field:cve.vulnStatus
Said since
2026-09-29 09:45 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2902c3ebcca52ca845c03182000e8d71d3a5196f",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "3439c15ae91a517cf3c650ea15a8987699416ad9",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "62708b9452f8eb77513115b17c4f8d1a22ebf843",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "6.0"
              },
              {
                "lessThan": "6.0",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.149",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.103",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.44",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.16.*",
                "status": "unaffected",
                "version": "6.16.4",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "6.17",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      },
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC CN 4100",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "V5.0",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
      }
    ],
    "cisaActionDue": "2026-09-21",
    "cisaExploitAdd": "2026-09-18",
    "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
    "cisaVulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability",
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "DE30211F-1A6B-457E-B19D-D3E385550199",
                "versionEndExcluding": "6.1.149",
                "versionStartIncluding": "6.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "F2293654-7169-49B5-8D0D-EE51EF8B8E48",
                "versionEndExcluding": "6.6.103",
                "versionStartIncluding": "6.2",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "12351F24-1133-4775-960C-F2B47E81298B",
                "versionEndExcluding": "6.12.44",
                "versionStartIncluding": "6.7",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AFC28995-B8C3-4B68-8CB6-78E792B6629D",
                "versionEndExcluding": "6.16.4",
                "versionStartIncluding": "6.13",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
                "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
                "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
                "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AA9D4F6E-9336-4026-B485-4227C861B356",
                "versionEndExcluding": "5.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          },
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*",
                "matchCriteriaId": "92619F5F-3679-4424-9455-3285FF1EF2F1",
                "vulnerable": false
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ],
        "operator": "AND"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntls: fix handling of zero-length records on the rx_list\n\nEach recvmsg() call must process either\n - only contiguous DATA records (any number of them)\n - one non-DATA record\n\nIf the next record has different type than what has already been\nprocessed we break out of the main processing loop. If the record\nhas already been decrypted (which may be the case for TLS 1.3 where\nwe don't know type until decryption) we queue the pending record\nto the rx_list. Next recvmsg() will pick it up from there.\n\nQueuing the skb to rx_list after zero-copy decrypt is not possible,\nsince in that case we decrypted directly to the user space buffer,\nand we don't have an skb to queue (darg.skb points to the ciphertext\nskb for access to metadata like length).\n\nOnly data records are allowed zero-copy, and we break the processing\nloop after each non-data record. So we should never zero-copy and\nthen find out that the record type has changed. The corner case\nwe missed is when the initial record comes from rx_list, and it's\nzero length."
      }
    ],
    "id": "CVE-2025-39682",
    "lastModified": "2026-09-21T12:00:36.613",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        },
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2025-39682",
            "options": [
              {
                "exploitation": "active"
              },
              {
                "automatable": "yes"
              },
              {
                "technicalImpact": "total"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-18T00:00:00+00:00",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2025-09-05T18:15:44.670",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677"
      },
      {
        "source": "af854a3a-2127-422b-91ae-364da2661108",
        "tags": [
          "Mailing List",
          "Third Party Advisory"
        ],
        "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
      },
      {
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
        "tags": [
          "Third Party Advisory"
        ],
        "url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html"
      },
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "tags": [
          "US Government Resource"
        ],
        "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39682"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Analyzed",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "NVD-CWE-Other"
          }
        ],
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-754"
          }
        ],
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ]
  }
}
—
Vendor
vendor
NVDLinux
receipt
Source
NVD
Its words
Linux
Read by
field:cve.affected[].affectedData[].vendor
Said since
2026-09-29 17:49 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
2026-09-29 17:49 UTCLinux
2026-09-29 09:45 UTC—
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2902c3ebcca52ca845c03182000e8d71d3a5196f",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "3439c15ae91a517cf3c650ea15a8987699416ad9",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              },
              {
                "lessThan": "62708b9452f8eb77513115b17c4f8d1a22ebf843",
                "status": "affected",
                "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "net/tls/tls_sw.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "6.0"
              },
              {
                "lessThan": "6.0",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.149",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.103",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.44",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.16.*",
                "status": "unaffected",
                "version": "6.16.4",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "6.17",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      },
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC CN 4100",
            "vendor": "Siemens",
            "versions": [
              {
                "lessThan": "V5.0",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
      }
    ],
    "cisaActionDue": "2026-09-21",
    "cisaExploitAdd": "2026-09-18",
    "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
    "cisaVulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability",
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "DE30211F-1A6B-457E-B19D-D3E385550199",
                "versionEndExcluding": "6.1.149",
                "versionStartIncluding": "6.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "F2293654-7169-49B5-8D0D-EE51EF8B8E48",
                "versionEndExcluding": "6.6.103",
                "versionStartIncluding": "6.2",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "12351F24-1133-4775-960C-F2B47E81298B",
                "versionEndExcluding": "6.12.44",
                "versionStartIncluding": "6.7",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AFC28995-B8C3-4B68-8CB6-78E792B6629D",
                "versionEndExcluding": "6.16.4",
                "versionStartIncluding": "6.13",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
                "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
                "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
                "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      },
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "AA9D4F6E-9336-4026-B485-4227C861B356",
                "versionEndExcluding": "5.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          },
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*",
                "matchCriteriaId": "92619F5F-3679-4424-9455-3285FF1EF2F1",
                "vulnerable": false
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ],
        "operator": "AND"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntls: fix handling of zero-length records on the rx_list\n\nEach recvmsg() call must process either\n - only contiguous DATA records (any number of them)\n - one non-DATA record\n\nIf the next record has different type than what has already been\nprocessed we break out of the main processing loop. If the record\nhas already been decrypted (which may be the case for TLS 1.3 where\nwe don't know type until decryption) we queue the pending record\nto the rx_list. Next recvmsg() will pick it up from there.\n\nQueuing the skb to rx_list after zero-copy decrypt is not possible,\nsince in that case we decrypted directly to the user space buffer,\nand we don't have an skb to queue (darg.skb points to the ciphertext\nskb for access to metadata like length).\n\nOnly data records are allowed zero-copy, and we break the processing\nloop after each non-data record. So we should never zero-copy and\nthen find out that the record type has changed. The corner case\nwe missed is when the initial record comes from rx_list, and it's\nzero length."
      }
    ],
    "id": "CVE-2025-39682",
    "lastModified": "2026-09-21T12:00:36.613",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        },
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 5.9,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2025-39682",
            "options": [
              {
                "exploitation": "active"
              },
              {
                "automatable": "yes"
              },
              {
                "technicalImpact": "total"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-18T00:00:00+00:00",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2025-09-05T18:15:44.670",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "tags": [
          "Patch"
        ],
        "url": "https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677"
      },
      {
        "source": "af854a3a-2127-422b-91ae-364da2661108",
        "tags": [
          "Mailing List",
          "Third Party Advisory"
        ],
        "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"
      },
      {
        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
        "tags": [
          "Third Party Advisory"
        ],
        "url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html"
      },
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "tags": [
          "US Government Resource"
        ],
        "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39682"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Analyzed",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "NVD-CWE-Other"
          }
        ],
        "source": "nvd@nist.gov",
        "type": "Primary"
      },
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-754"
          }
        ],
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ]
  }
}
—
Vendor project
vendor_project
CISA Known Exploited VulnerabilitiesLinux
receipt
Source
CISA Known Exploited Vulnerabilities
Its words
Linux
Read by
field:vendorProject
Said since
2026-09-28 11:44 UTC
Last answered
2026-10-05 14:19 UTC
What the source handed over
{
  "cveID": "CVE-2025-39682",
  "cwes": "CWE-754",
  "dateAdded": "2026-09-18",
  "dueDate": "2026-09-21",
  "forensicTriage": "Yes",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682",
  "product": "Kernel",
  "requiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.",
  "shortDescription": "Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.",
  "vendorProject": "Linux",
  "vulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"
}
—

vulnerability

Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability
zetlyn/cve-kev · 2026-09-18
cwes CWE-754 due_date 2026-09-21 exploited yes forensic_triage true known_ransomware_campaign_use Unknown product Kernel vendor_project Linux
kernel: tls: fix handling of zero-length records on the rx_list
zetlyn/cve-redhat · 2025-09-05
cvss 7 packages kernel-0:6.12.0-55.37.1.el10_0, kernel-0:5.14.0-570.49.1.el9_6, kernel-0:5.14.0-284.144.1.el9_2, kernel-rt-0:5.14.0-284.144.1.rt14.429.el9_2, kernel-0:5.14.0-427.96.1.el9_4 severity moderate source
In the Linux kernel, the following vulnerability has been resolved: tls: fix handling of zero-length records on the rx_list Each recvmsg() call must process either - only contiguous DATA records (any number of them) - one non-DATA record If the next record has different type than what has already been processed we break out of the main processing loop. If the record has already been decrypted (which may be the case for TLS 1.3 where we don't know type until decryption) we queue the pending record to the rx_list. Next recvmsg() will pick it up from there. Queuing the skb to rx_list after zero-copy decrypt is not possible, since in that case we decrypted directly to the user space buffer, and we don't have an skb to queue (darg.skb points to the ciphertext skb for access to metadata like length). Only data records are allowed zero-copy, and we break the processing loop after each non-data record. So we should never zero-copy and then find out that the record type has changed. The corner case we missed is when the initial record comes from rx_list, and it's zero length.
zetlyn/cve-nvd · 2025-09-05
cvss 9.8 product Linux status Analyzed vendor Linux source