CVE-2026-23849 (GCVE-0-2026-23849)

Vulnerability from cvelistv5 – Published: 2026-01-19 20:37 – Updated: 2026-01-20 15:54
VLAI
Title
File Browser vulnerable to Username Enumeration via Timing Attack in /api/login
Summary
File Browser provides a file managing interface within a specified directory and can be used to upload, delete, preview, rename, and edit files. Prior to version 2.55.0, 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. The vulnerability exists due to a "short-circuit" evaluation in the authentication logic. When a username is not found in the database, the function returns immediately. However, if the username does exist, the code proceeds to verify the password using bcrypt (users.CheckPwd), which is a computationally expensive operation designed to be slow. This difference in execution path creates a measurable timing discrepancy. Version 2.55.0 contains a patch for the issue.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-20 15:54 UTC
CWE
  • CWE-208 - Observable Timing Discrepancy
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
filebrowser filebrowser Affected: < 2.55.0
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