SiYuan: Unauthenticated Reflected XSS via SVG Injection in /api/icon/getDynamicIcon Endpoint

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

EPSS

• CVE-2026-29183: 0.70% estimated exploitation activity in the next 30 days; percentile 53.26 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary 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. Details The issue is caused by unsafe output construction and incomplete sanitization: 1. Endpoint is exposed without auth middleware - Source: https://github.com/siyuan-note/siyuan/blob/master/kernel/api/router.go#L27-L37 - GET /api/icon/getDynamicIcon is registered in the unauthenticated section. 2. User input is inserted into SVG via string formatting - Source: https://github.com/siyuan-note/siyuan/blob/master/kernel/api/icon.go#L115-L175 - Source:…

Published by the source

4 Mar 2026, 21:45 UTC

Last modified by the source

6 Mar 2026, 21:58 UTC

Source last checked

26 Oct 2026, 15:15 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-6865-qjcf-286f

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# Patch Next advisory brief: CVE-2026-29183

Advisory: SiYuan: Unauthenticated Reflected XSS via SVG Injection in /api/icon/getDynamicIcon Endpoint
IDs: CVE-2026-29183, GHSA-6865-qjcf-286f
Record: https://patchnext.com/advisories/cve-2026-29183 (revision 1, source checked 26 Oct 2026, 15:15 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/siyuan-note/siyuan/kernel 0.0.0-20260304034809-d68bd5a79391. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/siyuan-note/siyuan/kernel: affected < 0.0.0-20260304034809-d68bd5a79391; fixed in 0.0.0-20260304034809-d68bd5a79391

## Suggested inspection (read-only)
- Go github.com/siyuan-note/siyuan/kernel: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/siyuan-note/siyuan/kernel.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-6865-qjcf-286f (GitHub-reviewed advisory GHSA-6865-qjcf-286f lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260304034809-d68bd5a79391)

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