{"cve":"CVE-2026-66394","nvd":{"published":"2026-07-27T16:18:11.947","modified":"2026-10-24T13:10:00.147","status":"Deferred","description":"SiYuan before v3.7.3 contains stored and reflected cross-site scripting vulnerabilities in SVG sanitization that allows authenticated attackers to execute scripts by bypassing the HTML parser-based cleaner. Attackers can hide script tags within desc, style, or noscript elements which the HTML parser treats as raw text but browsers interpret as executable SVG content when served as image/svg+xml, enabling script execution in the application origin.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N","score":9.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","score":8.7},"cwes":["CWE-79"],"references":["https://github.com/siyuan-note/siyuan/security/advisories/GHSA-99rq-75j6-5j9f","https://www.vulncheck.com/advisories/siyuan-before-stored-and-reflected-xss-via-svg-sanitizer-bypass","https://github.com/siyuan-note/siyuan/security/advisories/GHSA-99rq-75j6-5j9f"],"products":[],"source":"nvd","synced_at":"2026-10-24T16:53:27.712498749+00:00"},"epss":{"cve":"CVE-2026-66394","score":0.00337,"percentile":0.26816,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-99rq-75j6-5j9f","url":"https://osv.dev/vulnerability/GHSA-99rq-75j6-5j9f","summary":"SiYuan: Stored and reflected XSS in SiYuan through an SVG sanitizer bypass","modified":"2026-09-10T15:25:27.534315099Z","packages":[{"ecosystem":"Go","name":"github.com/siyuan-note/siyuan/kernel","purl":"pkg:golang/github.com/siyuan-note/siyuan/kernel","ranges":["<0.0.0-20260714095344-f08dee71ba8e"],"fixed":["0.0.0-20260714095344-f08dee71ba8e"]}]},{"id":"GO-2026-6364","url":"https://osv.dev/vulnerability/GO-2026-6364","summary":"SiYuan: Stored and reflected XSS in SiYuan through an SVG sanitizer bypass in github.com/siyuan-note/siyuan/kernel","modified":"2026-09-10T15:25:27.534315099Z","packages":[{"ecosystem":"Go","name":"github.com/siyuan-note/siyuan/kernel","purl":"pkg:golang/github.com/siyuan-note/siyuan/kernel","ranges":["<0.0.0-20260714095344-f08dee71ba8e"],"fixed":["0.0.0-20260714095344-f08dee71ba8e"]}]}],"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."]}