Improper Handling of Case Sensitivity in FileBrowser - CVE-2026-25889
Published: April 8, 2026
Vulnerability identifier: #VU125389
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-25889
CWE-ID: CWE-178
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: File Browser
Affected software:
FileBrowser
FileBrowser
Detailed vulnerability description
The vulnerability allows a remote user to bypass current password verification and change a user's password.
The vulnerability exists due to improper handling of case sensitivity in the userPutHandler function in http/users.go when processing password update API requests. A remote user can send a specially crafted request using the Title Case field name "Password" to bypass current password verification and change a user's password.
The issue affects instances using the JSON authentication method, and administrators can use the same bypass to change any user's password.
How to mitigate CVE-2026-25889
Install security update from vendor's website.