CVE-2026-20800: Notification API Leaks Private Repository Issue Titles After Collaborator Permission Revocation

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% 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-200

Description

Gitea's notification API does not re-validate repository access permissions when returning notification details. After a user's access to a private repository is revoked, they may still view issue and pull request titles through previously received notifications.

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/36339
https://github.com/go-gitea/gitea/releases/tag/v1.25.4
https://github.com/go-gitea/gitea/security/advisories/GHSA-g54m-9f6g-wj7q

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