Executive brief
File Browser, a web-based file management interface, contains a vulnerability in its "hooks" system which allows users to run automated commands when files are uploaded or renamed. An attacker with permissions to upload or rename files can use specially crafted filenames to trick the server into executing unauthorized system commands. This could allow an attacker to take full control of the server, potentially leading to data theft or service disruption.
Technical details
The vulnerability exists in the hook system of File Browser (versions 2.0.0 through 2.33.7), specifically within the `Runner.exec` function in `runner/runner.go`. The application uses `os.Expand` to perform variable substitution for template strings like `$FILE` and `$USERNAME` without proper sanitization or escaping. An authenticated attacker with file write, upload, or rename permissions can craft a filename containing shell metacharacters (e.g., `; id #`). When a hook event (such as `after_upload`) triggers, the unsanitized filename is injected into a shell command string, leading to arbitrary Remote Code Execution (RCE). Starting with version 2.33.8, the command execution feature is disabled by default to mitigate this risk.
Affected products
- File Browser File Browser 2.0.0 to 2.33.7
Timeline
- 2025-06-25: other: Issue opened regarding faulty command execution features
- 2026-04-04: advisory: GitHub Security Advisory published
- 2026-04-07: disclosed: CVE published to NVD