CVE-2026-82654

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.

CVSS v3 8.9 HIGH

8.9^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-30 15:16

Updated : 2026-09-01 15:17

NVD link : CVE-2026-82654

Mitre link : CVE-2026-82654

CVE.ORG link : CVE-2026-82654

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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