CVE-2026-20888: Gitea Pull Requests Auto-Merge: Read-Only Users Can Cancel Scheduled Auto-Merge via Web Endpoint (Authorization Bypass)

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-01-22 · updated 2026-06-17
Weakness: CWE-284

Description

Gitea does not properly verify authorization when canceling scheduled auto-merges via the web interface. A user with read access to pull requests may be able to cancel auto-merges scheduled by other users.

Affected products

Gitea Open Source Git Server: before 1.25.4 — fixed in 1.25.4

How to fix

Upgrade to a fixed version: Gitea Open Source Git Server 1.25.4. Check the vendor advisory for mitigations.

References

https://blog.gitea.com/release-of-1.25.4/
https://github.com/go-gitea/gitea/pull/36341
https://github.com/go-gitea/gitea/pull/36356
https://github.com/go-gitea/gitea/releases/tag/v1.25.4
https://github.com/go-gitea/gitea/security/advisories/GHSA-ccq9-c5hv-cf64

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