{"id":"CVE-2026-54007","aliases":["GHSA-3vv5-8xxp-4f55","PYSEC-2026-2695"],"url":"https://o3.security/vulnerability/CVE-2026-54007","summary":"Open WebUI: Cross-origin postMessage confirmation bypass via action:submit","details":"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.","published":"2026-06-23T16:51:27.546Z","modified":"2026-08-12T03:51:35.394409314Z","cvss":null,"epss":{"score":0.00175,"percentile":0.07153,"asOf":"2026-08-12"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"open-webui","fixedVersion":"0.9.6"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54007.json"},{"type":"ADVISORY","url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-3vv5-8xxp-4f55"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54007"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:35.394409314Z"}}