CVE-2026-82654

critical · 9.3

SiYuan before v3.8.1 fails to properly escape block name, alias, and memo fields in hint, backlink, and breadcrumb rendering functions. Attackers can set a block's name to contain HTML/script tags that execute when another user views documents referencing or displaying that block.

9.3

CVSS

0.4%

EPSS (exploit prob.)

30th

EPSS percentile

2026-08-30

Published

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/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

Weaknesses

CWE-79

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-hf87-qh3j-3p88
https://www.vulncheck.com/advisories/siyuan-before-3.8.1-stored-xss-via-block-name

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-82654