In version 0.3.8 of open-webui/open-webui, an arbitrary file write vulnerability exists in the download_model endpoint. When deployed on Windows, the application improperly handles file paths, allowing an attacker to manipulate the file path to write files to arbitrary locations on the server's filesystem. This can result in overwriting critical system or application files, causing denial of service, or potentially achieving remote code execution (RCE). RCE can allow an attacker to execute malicious code with the privileges of the user running the application, leading to a full system compromise.
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize '\..\filename' (leading backslash dot dot) sequences that can resolve to a location that is outside of that directory.
| Link | Tags |
|---|---|
| https://huntr.com/bounties/7078261f-8414-4bb7-9d72-a2a4d8bfd5d1 | exploit third party advisory |