CVE-2026-72836
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.
Scoring
- Severity
- CRITICAL
- CVSS base score
- 9.2
- CVSS vector
- CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- EPSS probability
- 0.41%
- CWE
- CWE-178
- Published
- 2026-08-14
- Last modified
- 2026-08-18
Affected products
- filebrowser filebrowser
- filebrowser filebrowser
Weakness type
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