CVE-2026-29183 SiYuan: Unauthenticated Reflected XSS via SVG Injection in /api/icon/getDynamicIcon Endpoint
Unauthenticated reflected XSS in SiYuan allows attackers to execute arbitrary JavaScript via crafted SVG URLs, potentially leading to data exfiltration.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-29183?
CVE-2026-29183 is a critical cross-site scripting vulnerability in B3log Siyuan, published on 6 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
SiYuan is a personal knowledge management system. Prior to version 3.5.9, an unauthenticated reflected XSS vulnerability exists in the dynamic icon API endpoint "GET /api/icon/getDynamicIcon" when type=8, attacker-controlled content is embedded into SVG output without escaping. Because the endpoint is unauthenticated and returns image/svg+xml, a crafted URL can inject executable SVG/HTML event handlers (for example onerror) and run JavaScript in the SiYuan web origin. This can be chained to perform authenticated API actions and exfiltrate sensitive data when a logged-in user opens the malicious link. This issue has been patched in version 3.5.9.
Weakness: CWE-79
Which versions are affected by CVE-2026-29183?
3 open source packages ship an affected version, including github.com/siyuan-note/siyuan/kernel. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260304034809-d68bd5a79391 |
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260304034809-d68bd5a79391 |
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260304034809-d68bd5a79391 |
Products include B3log Siyuan.
How do I fix CVE-2026-29183?
Upgrade github.com/siyuan-note/siyuan/kernel to 0.0.0-20260304034809-d68bd5a79391 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-29183 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-29183 exists.
Public exploit code: 1 Nuclei template.
Other vulnerabilities in B3log Siyuan
- CVE-2026-32938 SiYuan has an Arbitrary File Read in its Desktop Publish Service
- CVE-2026-33669 SiYuan has Arbitrary Document Reading within the Publishing Service
- CVE-2026-33670 SiYuan has directory traversal within its publishing service
- CVE-2026-32767 SiYuan: Authorization Bypass Allows Arbitrary SQL Execution via Search API
- CVE-2024-53504 SQL injection in n/a
Sources
Also known as GHSA-6865-qjcf-286f, GO-2026-4596.