CVE-2026-93923

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan
https://github.com/siyuan-note/siyuan/blob/v3.8.4/app/src/util/Tree.ts#L133
https://github.com/siyuan-note/siyuan/blob/v3.8.4/app/src/util/Tree.ts#L194
https://github.com/siyuan-note/siyuan/blob/v3.8.4/kernel/model/render.go#L71-L76
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hfq-qwvx
https://www.vulncheck.com/advisories/siyuan-through-3.8.4-stored-xss-via-heading-style-attribute
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hfq-qwvx

Configurations

No configuration.

History

21 Sep 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hfq-qwvx -~~	() https://github.com/siyuan-note/siyuan/security/advisories/GHSA-928g-4hfq-qwvx -

19 Sep 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-19 00:16

Updated : 2026-09-21 16:17

NVD link : CVE-2026-93923

Mitre link : CVE-2026-93923

CVE.ORG link : CVE-2026-93923

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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