{"id":"CVE-2026-26247","sourceIdentifier":"88ee5874-cf24-4952-aea0-31affedb7ff2","published":"2026-07-03T21:16:58.417","lastModified":"2026-10-25T15:10:00.147","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"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."},{"lang":"es","value":"Las versiones de Gitea anteriores a la 1.25.5 no persisten correctamente el método de desafío OAuth2 PKCE S256 durante la autorización, permitiendo el intercambio de tokens sin la verificación del verificador esperada."}],"affected":[{"source":"88ee5874-cf24-4952-aea0-31affedb7ff2","affectedData":[{"vendor":"Gitea","product":"Gitea Open Source Git Server","defaultStatus":"unaffected","versions":[{"version":"0","lessThan":"1.25.5","versionType":"semver","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","baseScore":9.1,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE"},"exploitabilityScore":3.9,"impactScore":5.2}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-07T16:21:34.783006Z","id":"CVE-2026-26247","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"88ee5874-cf24-4952-aea0-31affedb7ff2","type":"Secondary","description":[{"lang":"en","value":"CWE-284"}]}],"references":[{"url":"https://blog.gitea.com/release-of-1.25.5/","source":"88ee5874-cf24-4952-aea0-31affedb7ff2"},{"url":"https://github.com/go-gitea/gitea/pull/36462","source":"88ee5874-cf24-4952-aea0-31affedb7ff2"},{"url":"https://github.com/go-gitea/gitea/pull/36477","source":"88ee5874-cf24-4952-aea0-31affedb7ff2"},{"url":"https://github.com/go-gitea/gitea/releases/tag/v1.25.5","source":"88ee5874-cf24-4952-aea0-31affedb7ff2"}]}