CVE-2026-45402

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, multiple endpoints accept a user-supplied file_id and attach the referenced file to a resource the caller controls (folder knowledge, knowledge-base contents) without verifying that the caller owns or has been granted access to the file. The file's content then becomes reachable through the downstream RAG / file-content paths, allowing any authenticated user to exfiltrate any other user's private file — and on the knowledge-base path, also to overwrite it — given knowledge of the file's UUID. This affects backend/open_webui/routers/folders.py (POST /api/v1/folders/{id}/update), backend/open_webui/routers/knowledge.py (add_file_to_knowledge_by_id), and backend/open_webui/routers/knowledge.py (add_files_to_knowledge_by_id_batch). This vulnerability is fixed in 0.9.5.
Configurations

Configuration 1 (hide)

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

History

18 May 2026, 19:53

Type Values Removed Values Added
First Time Openwebui
Openwebui open Webui
References () https://github.com/open-webui/open-webui/security/advisories/GHSA-r472-mw7m-967f - () https://github.com/open-webui/open-webui/security/advisories/GHSA-r472-mw7m-967f - Exploit, Mitigation, Vendor Advisory
CPE cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

15 May 2026, 23:16

Type Values Removed Values Added
References () https://github.com/open-webui/open-webui/security/advisories/GHSA-r472-mw7m-967f - () https://github.com/open-webui/open-webui/security/advisories/GHSA-r472-mw7m-967f -

15 May 2026, 21:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-05-15 21:16

Updated : 2026-05-18 19:53


NVD link : CVE-2026-45402

Mitre link : CVE-2026-45402

CVE.ORG link : CVE-2026-45402


JSON object : View

Products Affected

openwebui

  • open_webui
CWE
CWE-639

Authorization Bypass Through User-Controlled Key