open-webui Open WebUI up to 0.9.2 Audio Transcription Upload Endpoint transcriptions cross site scripting

Summaryinfo

A vulnerability identified as problematic has been detected in open-webui Open WebUI up to 0.9.2. Affected is an unknown function of the file CACHE_DIR/audio/transcriptions/ of the component Audio Transcription Upload Endpoint. Performing a manipulation results in cross site scripting. This vulnerability is known as CVE-2026-45315. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in open-webui Open WebUI up to 0.9.2. This affects some unknown functionality of the file CACHE_DIR/audio/transcriptions/ of the component Audio Transcription Upload Endpoint. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-45315 since 05/11/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 0.9.3 eliminates this vulnerability.

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Productinfo

Vendor

• open-webui

Name

• Open WebUI

Version

• 0.9.0
• 0.9.1
• 0.9.2

CPE 2.3info

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CPE 2.2info

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