CVE-2021-41599

Status: ModifiedHigh (8.8)—

A remote code execution vulnerability was identified in GitHub Enterprise Server that could be exploited when building a GitHub Pages site. To exploit this vulnerability, an attacker would need permission to create and build a GitHub Pages site on the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.3 and was fixed in versions 3.0.21, 3.1.13, 3.2.5. This vulnerability was reported via the GitHub Bug Bounty program.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 8.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 2.22%
Percentile among all scored CVEs: 82
Score date: 10/6/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Github — Enterprise Server

CWEs

CWE-77
NVD-CWE-noinfo

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2021-41599",
  "cveTags": [],
  "metrics": {
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          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:P",
          "authentication": "SINGLE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
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        "acInsufInfo": false,
        "impactScore": 6.4,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
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  "published": "2022-02-18T00:15:07.397",
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      "url": "https://docs.github.com/en/enterprise-server%403.1/admin/release-notes#3.1.13",
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      "url": "https://docs.github.com/en/enterprise-server%403.2/admin/release-notes#3.2.5",
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      "url": "https://docs.github.com/en/enterprise-server%403.0/admin/release-notes#3.0.21",
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      "source": "product-cna@github.com",
      "description": [
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          "value": "CWE-77"
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    {
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          "value": "NVD-CWE-noinfo"
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  "descriptions": [
    {
      "lang": "en",
      "value": "A remote code execution vulnerability was identified in GitHub Enterprise Server that could be exploited when building a GitHub Pages site. To exploit this vulnerability, an attacker would need permission to create and build a GitHub Pages site on the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.3 and was fixed in versions 3.0.21, 3.1.13, 3.2.5. This vulnerability was reported via the GitHub Bug Bounty program."
    },
    {
      "lang": "es",
      "value": "Se ha identificado una vulnerabilidad de ejecución de código remota en GitHub Enterprise Server que podía explotarse cuando era creado un sitio de GitHub Pages. Para explotar esta vulnerabilidad, un atacante necesitaría permiso para crear y construir un sitio de GitHub Pages en la instancia de GitHub Enterprise Server. Esta vulnerabilidad afectaba a todas las versiones de GitHub Enterprise Server anteriores a 3.3 y fue corregida en versiones 3.0.21, 3.1.13 y 3.2.5. Esta vulnerabilidad fue reportada por medio del programa GitHub Bug Bounty"
    }
  ],
  "lastModified": "2026-06-17T04:08:42.977",
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