6.0
Medium
CVE-2026-103620 A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed a repository…
Description
A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed a repository collaborator with write access to delete the current default branch through the GraphQL API and cause an attacker-controlled branch to become the new default. In repositories that required pull-request review but did not restrict branch deletion, this bypassed the review requirement and caused fresh clones and default-branch API requests to use attacker-controlled content. This vulnerability affected supported GitHub Enterprise Server releases in the 3.18, 3.19, 3.20, 3.21, and 3.22 series and was fixed in versions 3.18.16, 3.19.13, 3.20.9, 3.21.7, and 3.22.2. This vulnerability was reported via the GitHub Bug Bounty program.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Enterprise Server 3.22 | 3.22.0 → latest | No fix stated |
| Enterprise Server 3.21 | 3.21.0 → latest | No fix stated |
| Enterprise Server 3.20 | 3.20.0 → latest | No fix stated |
| Enterprise Server 3.19 | 3.19.0 → latest | No fix stated |
| Enterprise Server 3.18 | 3.18.0 → latest | No fix stated |
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Out-of-bounds read vulnerability in GitHub Enterprise Server allowed disclosure of process memory in the Git service
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Use-after-free vulnerability in GitHub Enterprise Server allowed remote code execution in the Git service
7.7
High
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A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed a…
8.7
High