Click-through XSS via incomplete SVG URI blocklist
Published Mar 20, 2026 · Updated Mar 20, 2026
Cross-site scripting in SiYuan 3.6.0 and earlier allows remote attackers to execute JavaScript through a crafted dynamic-icon URL. SanitizeSVG passes data:text/xml and data:application/xml href values because its blocklist omits those active-content MIME types, while getDynamicIcon inserts the content parameter into SVG markup without escaping. Exploitation requires a victim to open the endpoint directly or through object or embed content and click the injected link; ordinary image rendering does not expose the link.
Summary
What happened
Cross-site scripting in SiYuan 3.6.0 and earlier allows remote attackers to execute JavaScript through a crafted dynamic-icon URL. SanitizeSVG passes data:text/xml and data:application/xml href values because its blocklist omits those active-content MIME types, while getDynamicIcon inserts the content parameter into SVG markup without escaping. Exploitation requires a victim to open the endpoint directly or through object or embed content and click the injected link; ordinary image rendering does not expose the link.
The record
- CVE
- CVE-2026-32940
- Published
- Mar 20, 2026
- Updated
- Mar 20, 2026
- Vendor
- SiYuan Note
- Product
- SiYuan
- Classifications
- CWE-79, CWE-184, T1204.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 20, 2026CVE publishedPublication date reported by the CVE source.
- Mar 20, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 3.6.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Vendor advisory click-through XSS proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo