CVE-2026-45315

8.7 HIGH
Published: May 15, 2026 Modified: May 19, 2026
View on NVD

Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the audio transcription upload endpoint takes the file extension from the user-supplied filename and saves the file under CACHE_DIR/audio/transcriptions/.. The /cache/{path} route serves these files via FileResponse, which sets Content-Type from the on-disk extension and emits no Content-Disposition. A verified user with the default-on chat.stt permission can upload a polyglot WAV+HTML file named pwn.html and trick any other user into opening the resulting URL — the response comes back as text/html and any embedded <script> runs in the Open WebUI origin. This vulnerability is fixed in 0.9.3.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr
Source: security-advisories@github.com
Exploit Mitigation Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Exploit Mitigation Vendor Advisory

2 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.7 / 10.0
EPSS (Exploit Probability)
0.2%
8th percentile
Exploitation Status
Not in CISA KEV

Affected Vendors

openwebui