SiYuan before 3.8.4 renders document titles as HTML in the backlink dock tree without escaping markup characters. Attackers can set malicious titles through the rename API or crafted notebooks to execute scripts in the Electron renderer with access to child_process for command execution.
https://www.vulncheck.com/advisories/siyuan-before-3.8.4-cross-site-scripting-via-document-title
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-c5h9-g2c6-fxjw
https://github.com/siyuan-note/siyuan/commit/6f093ebe50afc503e2a8b056164293054f8509e7
https://github.com/siyuan-note/siyuan/blob/v3.8.3/app/src/util/Tree.ts#L134
Published: 2026-09-17
Updated: 2026-09-17
Base Score: 10
Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C
Severity: Critical
Base Score: 8.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.6
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00412