Open WebUI — Vulnerability (CVE-2026-54007)
Date: 2026-06
Affected: openwebui/open_webui
Attack vector: other
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-54007
CWE: CWE-346
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N)

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, the chat message listener allows non-same-origin input:prompt and action:submit messages, so an external site can set prompt text and trigger submitPrompt() in an authenticated victim session. I validated this with a cross-origin attacker page that auto-posted messages and caused unauthorized POST /api/v1/chats/new and POST /api/chat/completions requests containing attacker-controlled prompts. This enables cross-site forced actions and model/tool execution under victim privileges without consent. This vulnerability is fixed in 0.9.6.


Mitigations:

Architectural layers (MAESTRO):