Path traversal in Open WebUI - CVE-2026-28786
Published: April 24, 2026
Vulnerability identifier: #VU127477
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-28786
CWE-ID: CWE-22
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Open WebUI
Affected software:
Open WebUI
Open WebUI
Detailed vulnerability description
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to path traversal in POST /api/v1/audio/transcriptions when processing a crafted multipart filename. A remote user can send a specially crafted request to disclose sensitive information.
The issue leaks the server's absolute DATA_DIR path in the HTTP 400 response body, and the route is accessible to verified non-admin users.
How to mitigate CVE-2026-28786
Install security update from vendor's website.