Improper access control in FileBrowser - #VU139762

Detailed vulnerability description

The vulnerability allows a remote user to access protected routes and renew expired sessions.

The vulnerability exists due to improper access control in the shared authentication middleware when handling requests with an expired but validly signed JWT under proxy authentication with a non-default logout page. A remote user can present a previously valid signed token to access protected routes and renew expired sessions.

Administrative routes are affected when the token belongs to an administrator, and exploitation requires proxy authentication with a non-default auth.logoutPage configuration.

Remediation

Sources

• https://github.com/filebrowser/filebrowser/security/advisories/GHSA-v3jv-rmh2-635j
• https://github.com/filebrowser/filebrowser/commit/72faf6dd3c85628e332d3e567124b86708ce2695