CVE-2026-32940

SiYuan is a personal knowledge management system. In versions 3.6.0 and below, SanitizeSVG has an incomplete blocklist — it blocks data:text/html and data:image/svg+xml in href attributes but misses data:text/xml and data:application/xml, both of which can render SVG with JavaScript execution. The unauthenticated /api/icon/getDynamicIcon endpoint serves user-controlled input (via the content parameter) directly into SVG markup using fmt.Sprintf with no escaping, served as Content-Type: image/svg+xml. This creates a click-through XSS: a victim navigates to a crafted URL, sees an SVG with an injected link, and clicking it triggers JavaScript via the bypassed MIME types. The attack requires direct navigation to the endpoint or <object>/<embed> embedding, since <img> tag rendering in the frontend doesn't allow interactive links. This issue has been fixed in version 3.6.1.

CVSS v3 9.3 CRITICAL

9.3^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.8 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/advisories/GHSA-6865-qjcf-286f	Exploit Third Party Advisory
https://github.com/siyuan-note/siyuan/commit/d01d561875d4f744e9f6232f1d4831e3642b8696	Patch
https://github.com/siyuan-note/siyuan/releases/tag/v3.6.1	Release Notes
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4mx9-3c2h-hwhg	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-03-20 04:16

Updated : 2026-03-23 18:22

NVD link : CVE-2026-32940

Mitre link : CVE-2026-32940

CVE.ORG link : CVE-2026-32940

JSON object : View

Products Affected

b3log

siyuan

CWE

CWE-79

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

CWE-184

Incomplete List of Disallowed Inputs

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