{"cve":"CVE-2026-70492","nvd":{"published":"2026-08-04T21:16:38.190","modified":"2026-09-18T14:47:07.620","status":"Analyzed","description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.0, src/lib/components/chat/Messages/Markdown/KatexRenderer.svelte could store and render a chat message whose math block makes KaTeX fail with a stack overflow instead of a parse error. The catch branch fell back to inserting the original math source into the page as HTML through {@html} rather than as text, so script in the message runs in the browser of whoever views it, including shared chats and channels. The viewer's session token in localStorage can be stolen, and an administrator viewer can have their account taken over. This issue is fixed in 0.11.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","score":5.4},"cwes":["CWE-79"],"references":["https://github.com/open-webui/open-webui/commit/bc600d3f085802c45aa8f38c30e6e8c986bde6cc","https://github.com/open-webui/open-webui/pull/26718","https://github.com/open-webui/open-webui/releases/tag/v0.11.0","https://github.com/open-webui/open-webui/security/advisories/GHSA-pwxh-7358-jq2x","https://github.com/open-webui/open-webui/security/advisories/GHSA-pwxh-7358-jq2x"],"products":["openwebui:open_webui"],"source":"nvd","synced_at":"2026-10-19T22:47:10.050265369+00:00"},"epss":{"cve":"CVE-2026-70492","score":0.00403,"percentile":0.34576,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-pwxh-7358-jq2x","url":"https://osv.dev/vulnerability/GHSA-pwxh-7358-jq2x","summary":"Open WebUI: Stored XSS via unescaped KaTeX render-error fallback in rendered messages","modified":"2026-08-10T11:40:47.190156486Z","packages":[{"ecosystem":"PyPI","name":"open-webui","purl":"pkg:pypi/open-webui","ranges":[">=0.10.0 <0.11.0"],"fixed":["0.11.0"]}]},{"id":"PYSEC-2026-3650","url":"https://osv.dev/vulnerability/PYSEC-2026-3650","summary":"Open WebUI: Stored XSS via unescaped KaTeX render-error fallback in rendered messages","modified":"2026-08-10T11:30:11.567855381Z","packages":[{"ecosystem":"PyPI","name":"open-webui","purl":"pkg:pypi/open-webui","ranges":[">=0.10.0 <0.11.0"],"fixed":["0.11.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}