Information Exposure Through Timing Discrepancy in FileBrowser - CVE-2026-23849
Published: January 19, 2026 / Updated: June 5, 2026
Vulnerability identifier: #VU121644
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-23849
CWE-ID: CWE-208
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vulnerability details
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to the JSONAuth.Auth function contains a logic flaw. A remote attacker can measure the response time of the /api/login endpoint and enumerate valid usernames.
Affected software
FileBrowser
How to mitigate CVE-2026-23849
Install updates from vendor's website.
FileBrowser - update to 2.55.0