Description
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 malicious style values that execute in the Electron renderer with full system access.
References7
- github.com/siyuan-note/siyuan
- github.com/siyuan-note/siyuan/blob/v3.8.4/app/src/util/Tree.ts#…
- github.com/siyuan-note/siyuan/blob/v3.8.4/app/src/util/Tree.ts#…
- github.com/siyuan-note/siyuan/blob/v3.8.4/kernel/model/render.g…
- github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hf…
- www.vulncheck.com/advisories/siyuan-through-3.8.4-stored-xss-vi…
- github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hf…
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 4.0
-
8.6
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 49 · as of 8 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.