{"id":48541,"date":"2026-04-21T18:13:58","date_gmt":"2026-04-21T18:13:58","guid":{"rendered":"http:\/\/localhost\/?p=48541"},"modified":"2026-04-21T18:13:58","modified_gmt":"2026-04-21T18:13:58","slug":"improper-authorization-fallback-allows-scoped-user-to-server-token-installation-escape-in-github-ent","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=48541","title":{"rendered":"Improper authorization fallback allows scoped user-to-server token installation escape in GitHub Enterprise Server_CVE-2026-5845"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;An improper authorization vulnerability in scoped user-to-server (ghu_) token authorization in GitHub Enterprise Server allows an authenticated attacker to access private repositories outside the intended installation scope, which can include write operations, via an authorization fallback that treated a revoked\/deleted installation as a global installation context, which could be chained with token revocation timing and SSH push attribution to obtain and reuse a victim-scoped token. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, and 3.14.26. 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