CVE-2026-45315

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.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr	Exploit Mitigation Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-15 22:16

Updated : 2026-06-17 10:51

NVD link : CVE-2026-45315

Mitre link : CVE-2026-45315

CVE.ORG link : CVE-2026-45315

JSON object : View

Products Affected

openwebui

open_webui

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-434

Unrestricted Upload of File with Dangerous Type

CWE-646

Reliance on File Name or Extension of Externally-Supplied File

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