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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/filebrowser/filebrowser/commit/fe7efb2e6afe66774cd86a5b0a03033bd514d0c0
https://github.com/filebrowser/filebrowser/security/advisories/GHSA-576v-w77m-gr84
https://www.vulncheck.com/advisories/filebrowser-before-case-sensitivity-authentication-bypass
https://github.com/filebrowser/filebrowser/security/advisories/GHSA-576v-w77m-gr84

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-14 12:16

Updated : 2026-09-08 20:32

NVD link : CVE-2026-72836

Mitre link : CVE-2026-72836

CVE.ORG link : CVE-2026-72836

JSON object : View

Products Affected

No product.

CWE

CWE-178

Improper Handling of Case Sensitivity

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