CVE-2026-26247

Description

Gitea versions before 1.25.5 do not persist the OAuth2 PKCE S256 challenge method correctly during authorization, allowing token exchange without the expected verifier check.

References

• https://blog.gitea.com/release-of-1.25.5/
• https://github.com/go-gitea/gitea/pull/36462
• https://github.com/go-gitea/gitea/pull/36477
• https://github.com/go-gitea/gitea/releases/tag/v1.25.5