go-gitea/gitea · Security
Gitea OAuth2 PKCE S256 verifier bypass
- GHSA ID
- GHSA-m5ch-ppfx-xv3v
- CVE ID
- CVE-2026-26247
- Severity
- critical
- Published
- Updated
- CVSS
- 9.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- CVSS v3
- 9.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
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.
CWEs
- CWE-284 · Improper Access Control
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-26247 ↗
- https://github.com/go-gitea/gitea/pull/36462 ↗
- https://github.com/go-gitea/gitea/pull/36477 ↗
- https://blog.gitea.com/release-of-1.25.5 ↗
- https://github.com/go-gitea/gitea/releases/tag/v1.25.5 ↗
- https://github.com/go-gitea/gitea/commit/750649c1ef092c95f95b206b9d5fa17471a0b1f5 ↗
- https://github.com/go-gitea/gitea/commit/bf8d11bb212ba2a76596d8a90e74e7d664571324 ↗
- https://github.com/advisories/GHSA-m5ch-ppfx-xv3v ↗