{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-77912",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-77912",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-09-22T20:43:56.061Z",
    "updatedAt": "2026-09-23T15:05:17.200Z",
    "importedAt": "2026-10-24T01:58:30.346Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "Stored cross-site scripting vulnerability in GitHub Enterprise Server allowed HTML attribute injection via the Markdown rendering pipeline",
      "summary": "A stored cross-site scripting (XSS) vulnerability was identified in GitHub Enterprise Server that allowed an authenticated attacker to inject arbitrary HTML attributes into rendered Markdown because the Markdown rendering pipeline rewrote quote characters in already-sanitized HTML without re-sanitizing the result. Crafted Markdown could abuse same-origin JavaScript gadgets to bypass Content Security Policy and gain control of the page DOM when viewed by another user. Successful exploitation could allow an attacker to read content visible to the victim, extract embedded CSRF tokens, perform state-changing actions as the victim, and exfiltrate data through same-origin writes. The payload could also propagate to repositories and organizations where the victim had write access. This vulnerability affected supported GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, 3.21, and 3.22 series and was fixed in versions 3.22.1, 3.21.6, 3.20.8, 3.19.12, 3.18.15, and 3.17.21. This vulnerability was reported via the GitHub Bug Bounty program.",
      "affected": [
        {
          "vendor": "GitHub",
          "product": "Enterprise Server",
          "defaultStatus": "unknown",
          "versions": [
            {
              "version": "3.17.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "3.17.*",
              "changes": [
                {
                  "at": "3.17.21",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.18.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "3.18.*",
              "changes": [
                {
                  "at": "3.18.15",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.19.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "3.19.*",
              "changes": [
                {
                  "at": "3.19.12",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.20.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "3.20.*",
              "changes": [
                {
                  "at": "3.20.8",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.21.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "3.21.*",
              "changes": [
                {
                  "at": "3.21.6",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.22.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "3.22.*",
              "changes": [
                {
                  "at": "3.22.1",
                  "status": "unaffected"
                }
              ]
            }
          ]
        }
      ]
    }
  }
}