{"id":"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.","aliases":["GHSA-3vv5-8xxp-4f55"],"modified":"2026-07-08T08:13:47.843812217Z","published":"2026-06-23T16:51:27.546Z","database_specific":{"cwe_ids":["CWE-346"],"cna_assigner":"GitHub_M","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54007.json"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/open-webui/open-webui","events":[{"introduced":"0"},{"fixed":"1a97751e376e00a1897bc3679215ae1c7bd8fd42"}],"database_specific":{"source":["AFFECTED_FIELD","CPE_RANGE"],"cpe":"cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"0.9.6"}]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54007.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"}]}