cvedb.io
CVE-2026-1999
MEDIUM · CVSS 6.5
EPSS exploitation probability: 0%
Published 2026-02-18T21:16:24.147 · Last modified 2026-06-17T10:16:51.227

Summary

An incorrect authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to merge their own pull request into a repository without having push access by exploiting an authorization bypass in the enable_auto_merge mutation for pull requests. This issue only affected repositories that allow forking as the attack relies on opening a pull request from an attacker-controlled fork into the target repository. Exploitation was only possible in specific scenarios. It required a clean pull request status and only applied to branches without branch protection rules enabled. This vulnerability affected GitHub Enterprise Server versions prior to 3.19.2, 3.18.5, and 3.17.11, and was fixed in versions 3.19.2, 3.18.5, and 3.17.11. This vulnerability was reported via the

Affected products

github — enterprise_server

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.