Executive brief
File Browser, a web-based file management interface, contains a vulnerability that allows users with limited command permissions to execute unauthorized commands on the server. By using special characters like semicolons or pipes, an attacker can bypass security restrictions to run arbitrary code, potentially taking full control of the server. This feature is now disabled by default in newer versions to protect users.
Technical details
A command injection vulnerability exists in File Browser's command runner component due to improper neutralization of shell metacharacters. While the application validates the first token of user input against an allowlist, it subsequently passes the entire raw input string to the configured shell interpreter (e.g., /bin/sh -c). An authenticated attacker with 'Execute' permissions can use semicolons, pipes, or backticks to chain and execute arbitrary OS commands. This issue was addressed in version 2.33.8 by disabling the command execution feature by default; users must explicitly enable it and acknowledge the risks.
Affected products
- filebrowser File Browser < 2.33.8
Timeline
- 2026-06-03: advisory: GitHub security advisory published
- 2026-06-25: disclosed: CVE-2026-54090 published