CVE-2026-23849: File Browser Vulnerable to Username Enumeration via Timing Attack in /api/login

January 21, 2026

The JSONAuth.Auth function contains a logic flaw that allows unauthenticated attackers to enumerate valid usernames by measuring the response time of the /api/login endpoint.

References

github.com/advisories/GHSA-43mm-m3h2-3prc
github.com/filebrowser/filebrowser
github.com/filebrowser/filebrowser/commit/24781badd413ee20333aba5cce1919d676e01889
github.com/filebrowser/filebrowser/security/advisories/GHSA-43mm-m3h2-3prc
nvd.nist.gov/vuln/detail/CVE-2026-23849

Code Behaviors & Features

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