A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program.

cve CVE-2026-18730 1 source, 1 claim · Watch

NVD writes:
A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affec… the claim

What it is to other things

affectsgithub/enterprise_server
NVD
made_bygithub
NVD

What each source says

PropertySourceSaidMeans here
Cvss
cvss
NVD7.4
receipt
Source
NVD
Its words
7.4
Read by
field:cve.metrics.cvssMetricV31[].cvssData.baseScore
Said since
2026-09-29 09:45 UTC
Last answered
2026-10-04 18:16 UTC
Original
open at the source
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "Enterprise Server",
            "vendor": "GitHub",
            "versions": [
              {
                "changes": [
                  {
                    "at": "3.17.21",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.17.*",
                "status": "affected",
                "version": "3.17.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.18.15",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.18.*",
                "status": "affected",
                "version": "3.18.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.19.12",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.19.*",
                "status": "affected",
                "version": "3.19.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.20.8",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.20.*",
                "status": "affected",
                "version": "3.20.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.21.6",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.21.*",
                "status": "affected",
                "version": "3.21.0",
                "versionType": "semver"
              }
            ]
          }
        ],
        "source": "product-cna@github.com"
      }
    ],
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "384AEDA5-C4FB-4C1E-A158-C5824DC8C7E9",
                "versionEndExcluding": "3.17.19",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "209CD8A4-0690-4FBE-8FBF-D8DC01B4C5BA",
                "versionEndExcluding": "3.18.13",
                "versionStartIncluding": "3.18.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "E67B7806-5FA2-4E22-AC7E-5747D56AC167",
                "versionEndExcluding": "3.19.10",
                "versionStartIncluding": "3.19.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "86002896-8D6A-42EA-930C-D8E7C5DA3D70",
                "versionEndExcluding": "3.20.6",
                "versionStartIncluding": "3.20.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "54A93841-1037-4139-A61E-E23BDAB5DD8A",
                "versionEndExcluding": "3.21.4",
                "versionStartIncluding": "3.21.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program."
      }
    ],
    "id": "CVE-2026-18730",
    "lastModified": "2026-09-22T21:17:30.087",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 2.2,
          "impactScore": 5.2,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "cvssMetricV40": [
        {
          "cvssData": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "availabilityRequirement": "NOT_DEFINED",
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "confidentialityRequirement": "NOT_DEFINED",
            "exploitMaturity": "NOT_DEFINED",
            "integrityRequirement": "NOT_DEFINED",
            "modifiedAttackComplexity": "NOT_DEFINED",
            "modifiedAttackRequirements": "NOT_DEFINED",
            "modifiedAttackVector": "NOT_DEFINED",
            "modifiedPrivilegesRequired": "NOT_DEFINED",
            "modifiedSubAvailabilityImpact": "NOT_DEFINED",
            "modifiedSubConfidentialityImpact": "NOT_DEFINED",
            "modifiedSubIntegrityImpact": "NOT_DEFINED",
            "modifiedUserInteraction": "NOT_DEFINED",
            "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
            "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
            "modifiedVulnIntegrityImpact": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "source": "product-cna@github.com",
          "type": "Secondary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2026-18730",
            "options": [
              {
                "exploitation": "none"
              },
              {
                "automatable": "no"
              },
              {
                "technicalImpact": "partial"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-02T13:18:25.983888Z",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2026-09-01T22:17:10.850",
    "references": [
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.21"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.15"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.12"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.8"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.6"
      }
    ],
    "sourceIdentifier": "product-cna@github.com",
    "vulnStatus": "Modified",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-918"
          }
        ],
        "source": "product-cna@github.com",
        "type": "Secondary"
      }
    ]
  }
}
—
Product
product
NVDEnterprise Server
receipt
Source
NVD
Its words
Enterprise Server
Read by
field:cve.affected[].affectedData[].product
Said since
2026-09-29 17:49 UTC
Last answered
2026-10-04 18:16 UTC
Original
open at the source
2026-09-29 17:49 UTCEnterprise Server
2026-09-29 09:45 UTC—
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "Enterprise Server",
            "vendor": "GitHub",
            "versions": [
              {
                "changes": [
                  {
                    "at": "3.17.21",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.17.*",
                "status": "affected",
                "version": "3.17.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.18.15",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.18.*",
                "status": "affected",
                "version": "3.18.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.19.12",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.19.*",
                "status": "affected",
                "version": "3.19.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.20.8",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.20.*",
                "status": "affected",
                "version": "3.20.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.21.6",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.21.*",
                "status": "affected",
                "version": "3.21.0",
                "versionType": "semver"
              }
            ]
          }
        ],
        "source": "product-cna@github.com"
      }
    ],
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "384AEDA5-C4FB-4C1E-A158-C5824DC8C7E9",
                "versionEndExcluding": "3.17.19",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "209CD8A4-0690-4FBE-8FBF-D8DC01B4C5BA",
                "versionEndExcluding": "3.18.13",
                "versionStartIncluding": "3.18.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "E67B7806-5FA2-4E22-AC7E-5747D56AC167",
                "versionEndExcluding": "3.19.10",
                "versionStartIncluding": "3.19.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "86002896-8D6A-42EA-930C-D8E7C5DA3D70",
                "versionEndExcluding": "3.20.6",
                "versionStartIncluding": "3.20.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "54A93841-1037-4139-A61E-E23BDAB5DD8A",
                "versionEndExcluding": "3.21.4",
                "versionStartIncluding": "3.21.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program."
      }
    ],
    "id": "CVE-2026-18730",
    "lastModified": "2026-09-22T21:17:30.087",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 2.2,
          "impactScore": 5.2,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "cvssMetricV40": [
        {
          "cvssData": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "availabilityRequirement": "NOT_DEFINED",
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "confidentialityRequirement": "NOT_DEFINED",
            "exploitMaturity": "NOT_DEFINED",
            "integrityRequirement": "NOT_DEFINED",
            "modifiedAttackComplexity": "NOT_DEFINED",
            "modifiedAttackRequirements": "NOT_DEFINED",
            "modifiedAttackVector": "NOT_DEFINED",
            "modifiedPrivilegesRequired": "NOT_DEFINED",
            "modifiedSubAvailabilityImpact": "NOT_DEFINED",
            "modifiedSubConfidentialityImpact": "NOT_DEFINED",
            "modifiedSubIntegrityImpact": "NOT_DEFINED",
            "modifiedUserInteraction": "NOT_DEFINED",
            "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
            "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
            "modifiedVulnIntegrityImpact": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "source": "product-cna@github.com",
          "type": "Secondary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2026-18730",
            "options": [
              {
                "exploitation": "none"
              },
              {
                "automatable": "no"
              },
              {
                "technicalImpact": "partial"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-02T13:18:25.983888Z",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2026-09-01T22:17:10.850",
    "references": [
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.21"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.15"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.12"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.8"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.6"
      }
    ],
    "sourceIdentifier": "product-cna@github.com",
    "vulnStatus": "Modified",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-918"
          }
        ],
        "source": "product-cna@github.com",
        "type": "Secondary"
      }
    ]
  }
}
—
Status
status
NVDModified
receipt
Source
NVD
Its words
Modified
Read by
field:cve.vulnStatus
Said since
2026-09-29 09:45 UTC
Last answered
2026-10-04 18:16 UTC
Original
open at the source
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "Enterprise Server",
            "vendor": "GitHub",
            "versions": [
              {
                "changes": [
                  {
                    "at": "3.17.21",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.17.*",
                "status": "affected",
                "version": "3.17.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.18.15",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.18.*",
                "status": "affected",
                "version": "3.18.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.19.12",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.19.*",
                "status": "affected",
                "version": "3.19.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.20.8",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.20.*",
                "status": "affected",
                "version": "3.20.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.21.6",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.21.*",
                "status": "affected",
                "version": "3.21.0",
                "versionType": "semver"
              }
            ]
          }
        ],
        "source": "product-cna@github.com"
      }
    ],
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "384AEDA5-C4FB-4C1E-A158-C5824DC8C7E9",
                "versionEndExcluding": "3.17.19",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "209CD8A4-0690-4FBE-8FBF-D8DC01B4C5BA",
                "versionEndExcluding": "3.18.13",
                "versionStartIncluding": "3.18.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "E67B7806-5FA2-4E22-AC7E-5747D56AC167",
                "versionEndExcluding": "3.19.10",
                "versionStartIncluding": "3.19.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "86002896-8D6A-42EA-930C-D8E7C5DA3D70",
                "versionEndExcluding": "3.20.6",
                "versionStartIncluding": "3.20.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "54A93841-1037-4139-A61E-E23BDAB5DD8A",
                "versionEndExcluding": "3.21.4",
                "versionStartIncluding": "3.21.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program."
      }
    ],
    "id": "CVE-2026-18730",
    "lastModified": "2026-09-22T21:17:30.087",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 2.2,
          "impactScore": 5.2,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "cvssMetricV40": [
        {
          "cvssData": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "availabilityRequirement": "NOT_DEFINED",
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "confidentialityRequirement": "NOT_DEFINED",
            "exploitMaturity": "NOT_DEFINED",
            "integrityRequirement": "NOT_DEFINED",
            "modifiedAttackComplexity": "NOT_DEFINED",
            "modifiedAttackRequirements": "NOT_DEFINED",
            "modifiedAttackVector": "NOT_DEFINED",
            "modifiedPrivilegesRequired": "NOT_DEFINED",
            "modifiedSubAvailabilityImpact": "NOT_DEFINED",
            "modifiedSubConfidentialityImpact": "NOT_DEFINED",
            "modifiedSubIntegrityImpact": "NOT_DEFINED",
            "modifiedUserInteraction": "NOT_DEFINED",
            "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
            "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
            "modifiedVulnIntegrityImpact": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "source": "product-cna@github.com",
          "type": "Secondary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2026-18730",
            "options": [
              {
                "exploitation": "none"
              },
              {
                "automatable": "no"
              },
              {
                "technicalImpact": "partial"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-02T13:18:25.983888Z",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2026-09-01T22:17:10.850",
    "references": [
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.21"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.15"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.12"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.8"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.6"
      }
    ],
    "sourceIdentifier": "product-cna@github.com",
    "vulnStatus": "Modified",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-918"
          }
        ],
        "source": "product-cna@github.com",
        "type": "Secondary"
      }
    ]
  }
}
—
Vendor
vendor
NVDGitHub
receipt
Source
NVD
Its words
GitHub
Read by
field:cve.affected[].affectedData[].vendor
Said since
2026-09-29 17:49 UTC
Last answered
2026-10-04 18:16 UTC
Original
open at the source
2026-09-29 17:49 UTCGitHub
2026-09-29 09:45 UTC—
What the source handed over
{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unknown",
            "product": "Enterprise Server",
            "vendor": "GitHub",
            "versions": [
              {
                "changes": [
                  {
                    "at": "3.17.21",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.17.*",
                "status": "affected",
                "version": "3.17.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.18.15",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.18.*",
                "status": "affected",
                "version": "3.18.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.19.12",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.19.*",
                "status": "affected",
                "version": "3.19.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.20.8",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.20.*",
                "status": "affected",
                "version": "3.20.0",
                "versionType": "semver"
              },
              {
                "changes": [
                  {
                    "at": "3.21.6",
                    "status": "unaffected"
                  }
                ],
                "lessThan": "3.21.*",
                "status": "affected",
                "version": "3.21.0",
                "versionType": "semver"
              }
            ]
          }
        ],
        "source": "product-cna@github.com"
      }
    ],
    "configurations": [
      {
        "nodes": [
          {
            "cpeMatch": [
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "384AEDA5-C4FB-4C1E-A158-C5824DC8C7E9",
                "versionEndExcluding": "3.17.19",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "209CD8A4-0690-4FBE-8FBF-D8DC01B4C5BA",
                "versionEndExcluding": "3.18.13",
                "versionStartIncluding": "3.18.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "E67B7806-5FA2-4E22-AC7E-5747D56AC167",
                "versionEndExcluding": "3.19.10",
                "versionStartIncluding": "3.19.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "86002896-8D6A-42EA-930C-D8E7C5DA3D70",
                "versionEndExcluding": "3.20.6",
                "versionStartIncluding": "3.20.0",
                "vulnerable": true
              },
              {
                "criteria": "cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:*",
                "matchCriteriaId": "54A93841-1037-4139-A61E-E23BDAB5DD8A",
                "versionEndExcluding": "3.21.4",
                "versionStartIncluding": "3.21.0",
                "vulnerable": true
              }
            ],
            "negate": false,
            "operator": "OR"
          }
        ]
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program."
      }
    ],
    "id": "CVE-2026-18730",
    "lastModified": "2026-09-22T21:17:30.087",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 2.2,
          "impactScore": 5.2,
          "source": "nvd@nist.gov",
          "type": "Primary"
        }
      ],
      "cvssMetricV40": [
        {
          "cvssData": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "availabilityRequirement": "NOT_DEFINED",
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "confidentialityRequirement": "NOT_DEFINED",
            "exploitMaturity": "NOT_DEFINED",
            "integrityRequirement": "NOT_DEFINED",
            "modifiedAttackComplexity": "NOT_DEFINED",
            "modifiedAttackRequirements": "NOT_DEFINED",
            "modifiedAttackVector": "NOT_DEFINED",
            "modifiedPrivilegesRequired": "NOT_DEFINED",
            "modifiedSubAvailabilityImpact": "NOT_DEFINED",
            "modifiedSubConfidentialityImpact": "NOT_DEFINED",
            "modifiedSubIntegrityImpact": "NOT_DEFINED",
            "modifiedUserInteraction": "NOT_DEFINED",
            "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
            "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
            "modifiedVulnIntegrityImpact": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "source": "product-cna@github.com",
          "type": "Secondary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2026-18730",
            "options": [
              {
                "exploitation": "none"
              },
              {
                "automatable": "no"
              },
              {
                "technicalImpact": "partial"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-09-02T13:18:25.983888Z",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2026-09-01T22:17:10.850",
    "references": [
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.21"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.15"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.12"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.8"
      },
      {
        "source": "product-cna@github.com",
        "url": "https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.6"
      }
    ],
    "sourceIdentifier": "product-cna@github.com",
    "vulnStatus": "Modified",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-918"
          }
        ],
        "source": "product-cna@github.com",
        "type": "Secondary"
      }
    ]
  }
}
—

vulnerability

A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program.
zetlyn/cve-nvd · 2026-09-01
cvss 7.4 product Enterprise Server status Modified vendor GitHub source