In the Linux kernel, the following vulnerability has been resolved: vdpa_sim_blk: reject out-of-range sector starts vdpasim_blk_check_range() logs an invalid start sector but continues validating the request. The subsequent unsigned capacity subtraction can underflow and let an out-of-range buffer offset reach the data path. The invalid offset is used by three request paths. VIRTIO_BLK_T_OUT copies guest data to blk->buffer + offset through vringh_iov_pull_iotlb(), causing an out-of-bounds write in _copy_from_iter() or memcpy(). VIRTIO_BLK_T_IN copies from blk->buffer + offset to the guest through vringh_iov_push_iotlb(), causing an out-of-bounds read in _copy_to_iter(). VIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(), causing an out-of-bounds write. Reject starts at or beyond the capacity before the subtraction. Treat the capacity boundary as invalid because the IN and OUT paths round byte counts down to sectors for validation but later copy the original byte counts. A sub-sector request at the capacity boundary would otherwise still access past the end of the buffer. I found this bug myself, though the patch was written with AI assistance.

zetlyn/cve-nvd vulnerability cve CVE-2026-97991 known 2026-09-25

https://nvd.nist.gov/vuln/detail/CVE-2026-97991

Properties

cvss7.8
receipt
Source
NVD
Its words
7.8
Read by
field:cve.metrics.cvssMetricV31[type=Primary].cvssData.baseScore || field:cve.metrics.cvssMetricV31[].cvssData.baseScore
Said since
2026-09-29 09:45 UTC
Last answered
2026-10-06 12:41 UTC
Original
open at the source
What the source handed over
{
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    ],
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      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_blk: reject out-of-range sector starts\n\nvdpasim_blk_check_range() logs an invalid start sector but continues\nvalidating the request.  The subsequent unsigned capacity subtraction can\nunderflow and let an out-of-range buffer offset reach the data path.\n\nThe invalid offset is used by three request paths.  VIRTIO_BLK_T_OUT\ncopies guest data to blk->buffer + offset through\nvringh_iov_pull_iotlb(), causing an out-of-bounds write in\n_copy_from_iter() or memcpy().  VIRTIO_BLK_T_IN copies from\nblk->buffer + offset to the guest through vringh_iov_push_iotlb(),\ncausing an out-of-bounds read in _copy_to_iter().\nVIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(),\ncausing an out-of-bounds write.\n\nReject starts at or beyond the capacity before the subtraction.  Treat the\ncapacity boundary as invalid because the IN and OUT paths round byte counts\ndown to sectors for validation but later copy the original byte counts.  A\nsub-sector request at the capacity boundary would otherwise still access\npast the end of the buffer.\n\nI found this bug myself, though the patch was written with AI assistance."
      }
    ],
    "id": "CVE-2026-97991",
    "lastModified": "2026-10-03T11:18:22.853",
    "metrics": {
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          "cvssData": {
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            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
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          "exploitabilityScore": 1.1,
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          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        }
      ]
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    "published": "2026-09-25T11:17:27.220",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/000c6300776ceaf6b715780113f4275b1be4195b"
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        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Received"
  }
}
cvss_vectorCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
receipt
Source
NVD
Its words
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Read by
field:cve.metrics.cvssMetricV31[type=Primary].cvssData.vectorString || field:cve.metrics.cvssMetricV31[].cvssData.vectorString
Said since
2026-10-06 12:31 UTC
Last answered
2026-10-06 12:41 UTC
Original
open at the source
2026-10-06 12:31 UTCCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
2026-09-29 09:45 UTC—
What the source handed over
{
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            "product": "Linux",
            "programFiles": [
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            ],
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        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_blk: reject out-of-range sector starts\n\nvdpasim_blk_check_range() logs an invalid start sector but continues\nvalidating the request.  The subsequent unsigned capacity subtraction can\nunderflow and let an out-of-range buffer offset reach the data path.\n\nThe invalid offset is used by three request paths.  VIRTIO_BLK_T_OUT\ncopies guest data to blk->buffer + offset through\nvringh_iov_pull_iotlb(), causing an out-of-bounds write in\n_copy_from_iter() or memcpy().  VIRTIO_BLK_T_IN copies from\nblk->buffer + offset to the guest through vringh_iov_push_iotlb(),\ncausing an out-of-bounds read in _copy_to_iter().\nVIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(),\ncausing an out-of-bounds write.\n\nReject starts at or beyond the capacity before the subtraction.  Treat the\ncapacity boundary as invalid because the IN and OUT paths round byte counts\ndown to sectors for validation but later copy the original byte counts.  A\nsub-sector request at the capacity boundary would otherwise still access\npast the end of the buffer.\n\nI found this bug myself, though the patch was written with AI assistance."
      }
    ],
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}
productLinux
receipt
Source
NVD
Its words
Linux
Read by
field:cve.affected[].affectedData[].product
Said since
2026-09-29 17:49 UTC
Last answered
2026-10-06 12:41 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": [
          {
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            "product": "Linux",
            "programFiles": [
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    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_blk: reject out-of-range sector starts\n\nvdpasim_blk_check_range() logs an invalid start sector but continues\nvalidating the request.  The subsequent unsigned capacity subtraction can\nunderflow and let an out-of-range buffer offset reach the data path.\n\nThe invalid offset is used by three request paths.  VIRTIO_BLK_T_OUT\ncopies guest data to blk->buffer + offset through\nvringh_iov_pull_iotlb(), causing an out-of-bounds write in\n_copy_from_iter() or memcpy().  VIRTIO_BLK_T_IN copies from\nblk->buffer + offset to the guest through vringh_iov_push_iotlb(),\ncausing an out-of-bounds read in _copy_to_iter().\nVIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(),\ncausing an out-of-bounds write.\n\nReject starts at or beyond the capacity before the subtraction.  Treat the\ncapacity boundary as invalid because the IN and OUT paths round byte counts\ndown to sectors for validation but later copy the original byte counts.  A\nsub-sector request at the capacity boundary would otherwise still access\npast the end of the buffer.\n\nI found this bug myself, though the patch was written with AI assistance."
      }
    ],
    "id": "CVE-2026-97991",
    "lastModified": "2026-10-03T11:18:22.853",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 1.1,
          "impactScore": 6.0,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        }
      ]
    },
    "published": "2026-09-25T11:17:27.220",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/000c6300776ceaf6b715780113f4275b1be4195b"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/0a8693f00c408d85f086ad85d29e7030bf1e2055"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/14acb0d44b7d90a077beb7b92b444b90bafda9d9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/36ef4d8527f71648f00347f6ba759f0b7e5e0977"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/a8a1413a2cfdbedc896249f461d6d92efbbfe21f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Received"
  }
}
severityHIGH
From 7.0 to 8.9.
receipt
Source
NVD
Its words
HIGH
Read by
field:cve.metrics.cvssMetricV31[type=Primary].cvssData.baseSeverity || field:cve.metrics.cvssMetricV31[].cvssData.baseSeverity
Said since
2026-10-06 12:31 UTC
Last answered
2026-10-06 12:41 UTC
Original
open at the source
2026-10-06 12:31 UTCHIGH
2026-09-29 09:45 UTC—
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "drivers/vdpa/vdpa_sim/vdpa_sim_blk.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "36ef4d8527f71648f00347f6ba759f0b7e5e0977",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "000c6300776ceaf6b715780113f4275b1be4195b",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "14acb0d44b7d90a077beb7b92b444b90bafda9d9",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "a8a1413a2cfdbedc896249f461d6d92efbbfe21f",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "0a8693f00c408d85f086ad85d29e7030bf1e2055",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "drivers/vdpa/vdpa_sim/vdpa_sim_blk.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "5.13"
              },
              {
                "lessThan": "5.13",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "5.15.*",
                "status": "unaffected",
                "version": "5.15.222",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.189",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.158",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.111",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.53",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.7",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3-rc3",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_blk: reject out-of-range sector starts\n\nvdpasim_blk_check_range() logs an invalid start sector but continues\nvalidating the request.  The subsequent unsigned capacity subtraction can\nunderflow and let an out-of-range buffer offset reach the data path.\n\nThe invalid offset is used by three request paths.  VIRTIO_BLK_T_OUT\ncopies guest data to blk->buffer + offset through\nvringh_iov_pull_iotlb(), causing an out-of-bounds write in\n_copy_from_iter() or memcpy().  VIRTIO_BLK_T_IN copies from\nblk->buffer + offset to the guest through vringh_iov_push_iotlb(),\ncausing an out-of-bounds read in _copy_to_iter().\nVIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(),\ncausing an out-of-bounds write.\n\nReject starts at or beyond the capacity before the subtraction.  Treat the\ncapacity boundary as invalid because the IN and OUT paths round byte counts\ndown to sectors for validation but later copy the original byte counts.  A\nsub-sector request at the capacity boundary would otherwise still access\npast the end of the buffer.\n\nI found this bug myself, though the patch was written with AI assistance."
      }
    ],
    "id": "CVE-2026-97991",
    "lastModified": "2026-10-03T11:18:22.853",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 1.1,
          "impactScore": 6.0,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        }
      ]
    },
    "published": "2026-09-25T11:17:27.220",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/000c6300776ceaf6b715780113f4275b1be4195b"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/0a8693f00c408d85f086ad85d29e7030bf1e2055"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/14acb0d44b7d90a077beb7b92b444b90bafda9d9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/36ef4d8527f71648f00347f6ba759f0b7e5e0977"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/a8a1413a2cfdbedc896249f461d6d92efbbfe21f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Received"
  }
}
statusReceived
receipt
Source
NVD
Its words
Received
Read by
field:cve.vulnStatus
Said since
2026-09-29 09:45 UTC
Last answered
2026-10-06 12:41 UTC
Original
open at the source
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "drivers/vdpa/vdpa_sim/vdpa_sim_blk.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "36ef4d8527f71648f00347f6ba759f0b7e5e0977",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "000c6300776ceaf6b715780113f4275b1be4195b",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "14acb0d44b7d90a077beb7b92b444b90bafda9d9",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "a8a1413a2cfdbedc896249f461d6d92efbbfe21f",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "0a8693f00c408d85f086ad85d29e7030bf1e2055",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "drivers/vdpa/vdpa_sim/vdpa_sim_blk.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "5.13"
              },
              {
                "lessThan": "5.13",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "5.15.*",
                "status": "unaffected",
                "version": "5.15.222",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.189",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.158",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.111",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.53",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.7",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3-rc3",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_blk: reject out-of-range sector starts\n\nvdpasim_blk_check_range() logs an invalid start sector but continues\nvalidating the request.  The subsequent unsigned capacity subtraction can\nunderflow and let an out-of-range buffer offset reach the data path.\n\nThe invalid offset is used by three request paths.  VIRTIO_BLK_T_OUT\ncopies guest data to blk->buffer + offset through\nvringh_iov_pull_iotlb(), causing an out-of-bounds write in\n_copy_from_iter() or memcpy().  VIRTIO_BLK_T_IN copies from\nblk->buffer + offset to the guest through vringh_iov_push_iotlb(),\ncausing an out-of-bounds read in _copy_to_iter().\nVIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(),\ncausing an out-of-bounds write.\n\nReject starts at or beyond the capacity before the subtraction.  Treat the\ncapacity boundary as invalid because the IN and OUT paths round byte counts\ndown to sectors for validation but later copy the original byte counts.  A\nsub-sector request at the capacity boundary would otherwise still access\npast the end of the buffer.\n\nI found this bug myself, though the patch was written with AI assistance."
      }
    ],
    "id": "CVE-2026-97991",
    "lastModified": "2026-10-03T11:18:22.853",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 1.1,
          "impactScore": 6.0,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        }
      ]
    },
    "published": "2026-09-25T11:17:27.220",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/000c6300776ceaf6b715780113f4275b1be4195b"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/0a8693f00c408d85f086ad85d29e7030bf1e2055"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/14acb0d44b7d90a077beb7b92b444b90bafda9d9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/36ef4d8527f71648f00347f6ba759f0b7e5e0977"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/a8a1413a2cfdbedc896249f461d6d92efbbfe21f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Received"
  }
}
vendorLinux
receipt
Source
NVD
Its words
Linux
Read by
field:cve.affected[].affectedData[].vendor
Said since
2026-09-29 17:49 UTC
Last answered
2026-10-06 12:41 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": [
              "drivers/vdpa/vdpa_sim/vdpa_sim_blk.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "36ef4d8527f71648f00347f6ba759f0b7e5e0977",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "000c6300776ceaf6b715780113f4275b1be4195b",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "14acb0d44b7d90a077beb7b92b444b90bafda9d9",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "a8a1413a2cfdbedc896249f461d6d92efbbfe21f",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              },
              {
                "lessThan": "0a8693f00c408d85f086ad85d29e7030bf1e2055",
                "status": "affected",
                "version": "7d189f617f83f780915b737896a696ff605bd19f",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "drivers/vdpa/vdpa_sim/vdpa_sim_blk.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "5.13"
              },
              {
                "lessThan": "5.13",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "5.15.*",
                "status": "unaffected",
                "version": "5.15.222",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.189",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.158",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.111",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.53",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.7",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3-rc3",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvdpa_sim_blk: reject out-of-range sector starts\n\nvdpasim_blk_check_range() logs an invalid start sector but continues\nvalidating the request.  The subsequent unsigned capacity subtraction can\nunderflow and let an out-of-range buffer offset reach the data path.\n\nThe invalid offset is used by three request paths.  VIRTIO_BLK_T_OUT\ncopies guest data to blk->buffer + offset through\nvringh_iov_pull_iotlb(), causing an out-of-bounds write in\n_copy_from_iter() or memcpy().  VIRTIO_BLK_T_IN copies from\nblk->buffer + offset to the guest through vringh_iov_push_iotlb(),\ncausing an out-of-bounds read in _copy_to_iter().\nVIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(),\ncausing an out-of-bounds write.\n\nReject starts at or beyond the capacity before the subtraction.  Treat the\ncapacity boundary as invalid because the IN and OUT paths round byte counts\ndown to sectors for validation but later copy the original byte counts.  A\nsub-sector request at the capacity boundary would otherwise still access\npast the end of the buffer.\n\nI found this bug myself, though the patch was written with AI assistance."
      }
    ],
    "id": "CVE-2026-97991",
    "lastModified": "2026-10-03T11:18:22.853",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 1.1,
          "impactScore": 6.0,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        }
      ]
    },
    "published": "2026-09-25T11:17:27.220",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/000c6300776ceaf6b715780113f4275b1be4195b"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/0a8693f00c408d85f086ad85d29e7030bf1e2055"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/14acb0d44b7d90a077beb7b92b444b90bafda9d9"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/2ff2a8d063fdfa1e1479fb1fe2e3356a2ce89018"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/36ef4d8527f71648f00347f6ba759f0b7e5e0977"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/a8a1413a2cfdbedc896249f461d6d92efbbfe21f"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/d6dac17e20fd2abd0eb8c09d69fccf7426e12bcf"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Received"
  }
}

Text

In the Linux kernel, the following vulnerability has been resolved: vdpa_sim_blk: reject out-of-range sector starts vdpasim_blk_check_range() logs an invalid start sector but continues validating the request. The subsequent unsigned capacity subtraction can underflow and let an out-of-range buffer offset reach the data path. The invalid offset is used by three request paths. VIRTIO_BLK_T_OUT copies guest data to blk->buffer + offset through vringh_iov_pull_iotlb(), causing an out-of-bounds write in _copy_from_iter() or memcpy(). VIRTIO_BLK_T_IN copies from blk->buffer + offset to the guest through vringh_iov_push_iotlb(), causing an out-of-bounds read in _copy_to_iter(). VIRTIO_BLK_T_WRITE_ZEROES passes blk->buffer + offset to memset(), causing an out-of-bounds write. Reject starts at or beyond the capacity before the subtraction. Treat the capacity boundary as invalid because the IN and OUT paths round byte counts down to sectors for validation but later copy the original byte counts. A sub-sector request at the capacity boundary would otherwise still access past the end of the buffer. I found this bug myself, though the patch was written with AI assistance.