CVE-2026-103620

published 2026-10-06

CVE-2026-103620: A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed a repository collaborator with write access to delete the current…

Priority P3 36 medium 6 CVSS 4.0

AV N AC L AT P PR L UI N VC N VI H 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

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

5 ranges

Vendor	Product	Version range	Fixed in
github	enterprise_server	>= 3.18.0 < 3.18.*	3.18.*
github	enterprise_server	>= 3.19.0 < 3.19.*	3.19.*
github	enterprise_server	>= 3.20.0 < 3.20.*	3.20.*
github	enterprise_server	>= 3.21.0 < 3.21.*	3.21.*
github	enterprise_server	>= 3.22.0 < 3.22.*	3.22.*

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CWE-862