{"id":"CVE-2026-93923","title":"SiYuan through 3.8.4 fails to escape heading style attributes when rendering outline and bookmark dock HTML, allowing stored cross-site scripting","summary":"SiYuan through 3.8.4 fails to escape heading style attributes when rendering outline and bookmark dock HTML, allowing stored cross-site scripting. Attackers can supply crafted notebooks or call administrative endpoints to inject maliciou…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cwe":["CWE-79"],"vendor":"siyuan-note","product":"github.com/siyuan-note/siyuan/kernel","affected":["github.com/siyuan-note/siyuan/kernel <= 3.8.4"],"published":"2026-09-19","updated":"2026-09-21","sourceUpdated":"2026-09-21T16:17:28.387","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93923","references":[{"url":"https://github.com/siyuan-note/siyuan","label":"disclosure@vulncheck.com"},{"url":"https://github.com/siyuan-note/siyuan/blob/v3.8.4/app/src/util/Tree.ts#L133","label":"disclosure@vulncheck.com"},{"url":"https://github.com/siyuan-note/siyuan/blob/v3.8.4/app/src/util/Tree.ts#L194","label":"disclosure@vulncheck.com"},{"url":"https://github.com/siyuan-note/siyuan/blob/v3.8.4/kernel/model/render.go#L71-L76","label":"disclosure@vulncheck.com"},{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hfq-qwvx","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/siyuan-through-3.8.4-stored-xss-via-heading-style-attribute","label":"disclosure@vulncheck.com"},{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hfq-qwvx","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd","cve.org","exploit-available"],"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"total","timestamp":"2026-09-21T15:38:34.747243Z"},"epss":0.00415,"epssPercentile":0.3534,"ingestedAt":"2026-09-18T23:54:36.626Z","slug":"CVE-2026-93923","body":"## Overview\n\nSiYuan through 3.8.4 fails to escape heading style attributes when rendering outline and bookmark dock HTML, allowing stored cross-site scripting. Attackers can supply crafted notebooks or call administrative endpoints to inject malicious style values that execute in the Electron renderer with full system access.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":60,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":208531,"id":"CVE-2026-93923","ts":1790007770808,"field":"exploit_available","old":"false","new":"true"}]}