{"id":"CVE-2026-87811","title":"SiYuan before v3.8.2 inserts persisted notebook template paths into HTML input value attributes without proper attribute encoding","summary":"SiYuan before v3.8.2 inserts persisted notebook template paths into HTML input value attributes without proper attribute encoding. Attackers can craft malicious template paths that break out of the attribute context and execute JavaScrip…","severity":"high","cvss":7.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N","cwe":["CWE-79"],"vendor":"siyuan-note","product":"siyuan","affected":["siyuan < 3.8.2"],"published":"2026-09-09","updated":"2026-09-09","sourceUpdated":"2026-09-09T20:20:21.673","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-87811","references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-v6wf-r2gr-rrgf","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/siyuan-before-3.8.2-stored-xss-via-notebook-template-paths","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org","exploit-available"],"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"total","timestamp":"2026-09-09T12:18:24.227560Z"},"ingestedAt":"2026-09-14T10:09:14.762Z","epss":0.00207,"epssPercentile":0.11098,"slug":"CVE-2026-87811","body":"## Overview\n\nSiYuan before v3.8.2 inserts persisted notebook template paths into HTML input value attributes without proper attribute encoding. Attackers can craft malicious template paths that break out of the attribute context and execute JavaScript when a victim opens notebook configuration, enabling same-origin API requests and application state manipulation.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":52,"depthScoreParts":{"impact":40.2,"likelihood":0,"exploitation":12,"ransomware":0},"changes":[{"seq":16170,"id":"CVE-2026-87811","ts":1788959420405,"field":"exploit_available","old":"false","new":"true"}]}