CVE-2026-82654

HIGH 8.9

SiYuan before v3.8.1 Stored XSS via block name

CVSS Score

8.9

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-79
Vendor	siyuan-note
Product	siyuan
Published	Aug 30, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

Low

Affected Versions

siyuan-note / siyuan

0 < 3.8.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

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

Credits

🔍 alham-rizvi 🔍 crypto-nidh