CVE-2026-26247: critical vulnerability in Gitea Open Source Git Server
Gitea OAuth2 PKCE S256 challenges are not enforced during token exchange
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Gitea · Gitea Open Source Git ServerRelated CVEs — Gitea Open Source Git Server
In the same product, most dangerous first.
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