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TI-2021-05722 Aliases CVE-2021-22861GHSA-x87g-4c45-mvv5

Improper access control in GitHub Enterprise Server leading to unauthorized write access to forkable repositories

Priority LOW 31CWE-285Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-285.

Summary

An improper access control vulnerability was identified in GitHub Enterprise Server that allowed authenticated users of the instance to gain write access to unauthorized repositories via specifically crafted pull requests and REST API requests. An attacker would need to be able to fork the targeted repository, a setting that is disabled by default for organization owned private repositories. Branch protections such as required pull request reviews or status checks would prevent unauthorized commits from being merged without further review or validation. This vulnerability affected all versions of GitHub Enterprise Server since 2.4.21 and was fixed in versions 2.20.24, 2.21.15, 2.22.7 and 3.0.1. This vulnerability was reported via the GitHub Bug Bounty program.

Why it matters now

EPSS 0.00952 61st percentileScored 2026-11-07
Fix Fixed GitHub Enterprise Server (GitHub): 2.20.24, 2.21.15, 2.22.7 +1

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
GitHubGitHub Enterprise Server2.20 to before 2.20.24; 2.21 to before 2.21.15; 2.22 to before 2.22.7; 3.0 to before 3.0.12.20.24, 2.21.15, 2.22.7, 3.0.1Patch availableCNA
  • GitHub Enterprise Server VendorGitHub Affected 2.20 to before 2.20.24; 2.21 to before 2.21.15; 2.22 to before 2.22.7; 3.0 to before 3.0.1 Fixed in 2.20.24, 2.21.15, 2.22.7, 3.0.1 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:github:github:*:*:*:*:enterprise:*:*:*2.4.21 to before 2.20.24; 2.21.0 to before 2.21.15; 2.22.0 to before 2.22.7VulnerableGitHub
cpe:2.3:a:github:github:*:*:*:*:*:*:*:*3.0.0 to before 3.0.1VulnerableGitHub
  • cpe:2.3:a:github:github:*:*:*:*:enterprise:*:*:* Versions 2.4.21 to before 2.20.24; 2.21.0 to before 2.21.15; 2.22.0 to before 2.22.7 Vulnerable ·GitHub
  • cpe:2.3:a:github:github:*:*:*:*:*:*:*:* Versions 3.0.0 to before 3.0.1 Vulnerable ·GitHub

Remediation

  • Fix · CNA GitHub Enterprise Server (GitHub) Fixed in 2.20.24, 2.21.15, 2.22.7, 3.0.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    GitHub Enterprise Server 2.20.24, 2.21.15 and 2 more versions

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2021-05724 Improper authorization in GitHub Enterprise ServerPriority LOW 37
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-22861
  2. 2026-10-03 Alias added: GHSA-x87g-4c45-mvv5

References

Other 4

  • TI-2017-13538 The Management Console in GitHub Enterprise 2.8.x before 2.8.7 has a deserialization… CVSS 3.0CRITICAL 9.8
  • TI-2020-08450 Improper access control in GitHub Enterprise Server leading to privilege escalation of organization member CVSS 3.1CRITICAL 9.8
  • TI-2020-08453 Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server CVSS 3.1HIGH 8.8
  • TI-2020-08452 Unsafe configuration options in GitHub Pages leading to remote code execution on GitHub Enterprise Server CVSS 3.1HIGH 8.8
  • TI-2021-05724 Improper authorization in GitHub Enterprise Server CVSS 3.1HIGH 8.1
  • TI-2012-01828 GitHub Enterprise before 20120304 does not properly restrict the use of a hash to provide… CVSS 3.1HIGH 7.5
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences