{"schema":"threatline.record/2","record":{"id":"CVE-2026-109300","aliases":["GHSA-9wj4-mcm3-ppj6"],"summary":"Open WebUI 0.6.31 before 0.11.4 Stored XSS via Tool-Call Embeds","details":"Open WebUI from 0.6.31 before 0.11.4 contains a stored cross-site scripting vulnerability in its Markdown renderer, which treats user-authored tool-call details blocks as tool output and mounts their embeds attribute in script-enabled iframes. Authenticated users can post crafted channel messages, chat messages, or citation content that runs JavaScript in viewers' browsers, enabling in-app phishing, or session hijacking where iframeSandboxAllowSameOrigin is enabled.","categories":["Unclassified"],"product":"open-webui","vendor":"open-webui","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-109300","source_modified_at":"2026-10-13T18:09:47.634Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"open-webui","vendor":"open-webui","versions":[{"version":"0.6.31","status":"affected","versionType":"semver","lessThan":"0.11.4"},{"version":"0.11.4","status":"unaffected","versionType":"semver"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-109300","source_modified_at":"2026-10-13T18:09:47.634Z","fetched_at":"2026-10-23T18:48:36.087640Z","package":{"name":"open-webui","ecosystem":null},"version":"0.11.4","basis":"first unaffected version stated in the CVE record"}],"cvss":5.1,"severity":"Medium","kev":{"listed":false},"epss":{"probability":0.00179,"percentile":0.07054,"score_date":"2026-10-23"},"published_at":"2026-10-12T16:04:58.200Z","modified_at":"2026-10-13T18:09:47.634Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-109300","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-13T18:09:47.634Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-109300","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-9wj4-mcm3-ppj6","tags":["exploit"]},{"source":"CVE List","url":"https://www.vulncheck.com/advisories/open-webui-0.6.31-before-0.11.4-stored-xss-via-tool-call-embeds","tags":["third-party-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"poc","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-13T18:09:25.448143Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-13T18:09:47.634Z","content_hash":"b299e98f4991a721519504a7fef270cff1d6313b46bd38276d5f44e5b6df5755"}}