Vulnerability · Published Mar 31, 2026 · Assigned by GitHub_M
CVE-2026-34605SiYuan: Reflected XSS via SVG namespace prefix bypass in SanitizeSVG ( getDynamicIcon, unauthenticated )
High 8.6
In plain English
A high-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 0.5% (higher than 41% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei. Fixed versions are available - upgrade the affected package.
Official description
SiYuan is a personal knowledge management system. From version 3.6.0 to before version 3.6.2, the SanitizeSVG function introduced in version 3.6.0 to fix XSS in the unauthenticated /api/icon/getDynamicIcon endpoint can be bypassed by using namespace-prefixed element names such as <x:script xmlns:x="http://www.w3.org/2000/svg">. The Go HTML5 parser records the element's tag as "x:script" rather than "script", so the tag check passes it through. The SVG is served with Content-Type: image/svg+xml and no Content Security Policy; when a browser opens the response directly, its XML parser resolves the prefix to the SVG namespace and executes the embedded script. This issue has been patched in version 3.6.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/siyuan-note/siyuan/kernel | 0.0.0-20260330031106-f09953afc57a | GHSA-73g7-86qr-jrg3 |
| Go | github.com/siyuan-note/siyuan/kernel | 0.0.0-20260330031106-f09953afc57a | GO-2026-5201 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| siyuan-note | siyuan | >= 3.6.0, < 3.6.2 |
Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N
References
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-73g7-86qr-jrg3 x_refsource_CONFIRM
- https://github.com/siyuan-note/siyuan/issues/17246 x_refsource_MISC
- https://github.com/siyuan-note/siyuan/releases/tag/v3.6.2 x_refsource_MISC