CVE-2026-54007: open-webui Origin Validation Error

Vulnerability summary

CVE-2026-54007 is a high (CVSS 7.1) Origin Validation Error vulnerability in open-webui. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 23-06-2026
   PublishedVulnerability first disclosed.
2. 26-06-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-346Origin Validation ErrorThe product does not properly verify that the source of data or communication is valid.