CVE-2026-74902
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 containing script payloads that execute with full OS command access when a user drags, drops, or pastes the file into the editor.
- Score
- CVSS 4.0 9.3 Critical
- Status
- Deferred - disclosure@vulncheck.com
- Published
- 2026-08-18
- Last modified
- 2026-10-22
- Weaknesses
- CWE-79
Affected products
References
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jf56-jrhq-j2qp
- https://www.vulncheck.com/advisories/siyuan-before-xss-to-rce-via-malicious-filename-upload
