CVE-2026-72836: Filebrowser

High severity, CVSS 8.1. EPSS: 0.6% chance of exploitation in the next 30 days.

FileBrowser before 2.63.19 does not account for case-insensitive filesystems when checking home directory ownership during self-registration. When Signup and CreateUserDir are enabled and FileBrowser's root is on a case-insensitive filesystem (confirmed on Windows/NTFS), two self-registered usernames that differ only in letter case (e.g., CaseVictim and casevictim) are stored as distinct accounts but resolve to the same physical home directory, because the scope-ownership check compares the persisted scope as an exact case-sensitive string. A second registrant can therefore read, overwrite, and delete another account's files through authenticated HTTP endpoints, without needing an existing account or victim interaction.

Affected products

• Filebrowser Filebrowser: before 2.63.19 (fixed in 2.63.19)

Published 2026-08-14. Last modified 2026-09-08.