CVE-2026-31807

SiYuan is a personal knowledge management system. Prior to 3.5.10, SiYuan's SVG sanitizer (SanitizeSVG) blocks dangerous elements (<script>, <iframe>, <foreignobject>) and removes on* event handlers and javascript: in href attributes. However, it does NOT block SVG animation elements (<animate>, <set>) which can dynamically set attributes to dangerous values at runtime, bypassing the static sanitization. This allows an attacker to inject executable JavaScript into the unauthenticated /api/icon/getDynamicIcon endpoint (type=8), creating a reflected XSS. This is a bypass of the fix for CVE-2026-29183 (fixed in v3.5.9). This vulnerability is fixed in v3.5.10.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5hc8-qmg8-pw27	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-10 21:16

Updated : 2026-03-11 20:16

NVD link : CVE-2026-31807

Mitre link : CVE-2026-31807

CVE.ORG link : CVE-2026-31807

JSON object : View

Products Affected

b3log

siyuan

CWE

CWE-79

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

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