Vulnerability · Published Mar 20, 2026 · Assigned by GitHub_M

CVE-2026-32940SiYuan has a SanitizeSVG bypass via data:text/xml in getDynamicIcon (incomplete fix for CVE-2026-29183)

Critical 9.3

In plain English

A critical-severity cross-site scripting in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).

Severity (CVSS 3.1)9.3Critical

Exploit odds (30 days)0.3%top 75.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/siyuan-note/siyuan	no fix listed	GHSA-4mx9-3c2h-hwhg
Go	github.com/siyuan-note/siyuan	no fix listed	GO-2026-4721

Affected products (as reported)

Vendor	Product	Versions
siyuan-note	siyuan	< 3.6.1

Weakness: CWE-79, CWE-184 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4mx9-3c2h-hwhg x_refsource_CONFIRM
https://github.com/siyuan-note/siyuan/commit/d01d561875d4f744e9f6232f1d4831e3642b8696 x_refsource_MISC
https://github.com/advisories/GHSA-6865-qjcf-286f x_refsource_MISC
https://github.com/siyuan-note/siyuan/releases/tag/v3.6.1 x_refsource_MISC