{"id":"CVE-2026-74902","title":"SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file upload validation flow that fails to escape filenames before inserting them into HTML via insertAdjacentHTML","summary":"SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file upload validation flow that fails to escape filenames before inserting them into HTML via insertAdjacentHTML. Attackers can craft a malicious filename contain…","severity":"high","cvss":8.6,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H","cwe":["CWE-79"],"vendor":"siyuan-note","product":"siyuan","affected":["siyuan < 3.7.4"],"published":"2026-08-18","updated":"2026-10-08","sourceUpdated":"2026-10-08T16:17:40.330","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74902","references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jf56-jrhq-j2qp","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/siyuan-before-xss-to-rce-via-malicious-filename-upload","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-08-18T12:52:00.846926Z"},"epss":0.00198,"epssPercentile":0.08786,"ingestedAt":"2026-10-08T16:52:14.721Z","slug":"CVE-2026-74902","body":"## Overview\n\nSiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file upload validation flow that fails to escape filenames before inserting them into HTML via insertAdjacentHTML. Attackers can craft a malicious filename containing script payloads that execute with full OS command access when a user drags, drops, or pastes the file into the editor.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":47,"depthScoreParts":{"impact":47.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}