CVE-2026-20896 — Updated!

CVE-2026-20896: Gitea Docker Image Authentication Bypass PoC !WARNING Use this PoC only in a local lab or against a system you are explicitly authorized to test. https://github.com/user-attachments/assets/b73af2fe-0e59-438b-80d6-be93fd75697b Overview CVE-2026-20896 is an authentication bypass in...

Gitea Docker image: `REVERSE_PROXY_TRUSTED_PROXIES = *` default lets any source IP impersonate any user via `X-WEBAUTH-USER`

Summary The Gitea Docker images ship an app.ini template that hard-codes: REVERSEPROXYTRUSTEDPROXIES = The documented default for this setting, in custom/conf/app.example.ini, is 127.0.0.0/8,::1/128, i.e. only loopback is trusted. When an admin enables ENABLEREVERSEPROXYAUTHENTICATION = true to p...

CVE-2026-20896

Gitea Docker images up to 1.26.2 ship REVERSE_PROXY_TRUSTED_PROXIES = *, which allows any source IP to spoof and impersonate a user via X-WEBAUTH-USER when reverse-proxy authentication is enabled. This affects gitea/gitea:1.26.2 and related Docker templates, enabling unauthenticated impersonation...