# CVE-2026-93921: SiYuan access control bypass in getDynamicIcon endpoint

Source: https://junglewise.ai/threats/cve-2026-93921-siyuan-versions-through-3-8-4-fail-to-enforce-publish-access  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-19. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-93921 · Severity: medium · CVSS 4.3 · Published 2026-09-19

SiYuan is an open-source knowledge management and note-taking workspace application. An access control vulnerability in versions through 3.8.4 allows users with read-only access tokens to retrieve sensitive document metadata (titles, names, aliases, and document hierarchies) that should be restricted. An attacker with a limited read-only token can exploit template injection to access confidential document information.

Technologies: [SiYuan Note SiYuan](https://junglewise.ai/threats/technologies/siyuan-note-siyuan). Vendors: [SiYuan Note](https://junglewise.ai/threats/vendors/siyuan-note).

## Quick answers

**Is CVE-2026-93921 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-93921 being exploited in the wild.

**How severe is CVE-2026-93921?** Medium severity, with a CVSS score of 4.3, published 19 September 2026.

**Which products and versions are affected?** SiYuan Note SiYuan through 3.8.4.

**Is there a fix for CVE-2026-93921?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-93921 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-93921?** Check whether you run SiYuan Note SiYuan at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The getDynamicIcon endpoint fails to enforce publish access control, allowing read-only token holders to inject crafted content with type=8 parameters to trigger template injection. This enables unauthorized metadata extraction including block titles, names, aliases, and hierarchical paths of restricted documents. The vulnerability requires network access and a valid read-only token, and no user interaction is necessary.

## Affected products

- SiYuan Note SiYuan through 3.8.4

## Timeline

- 2026-09-19: disclosed

## References

- [https://pkg.go.dev/](https://pkg.go.dev/)
- [https://github.com/siyuan-note/siyuan](https://github.com/siyuan-note/siyuan)

## Related threats

- [SiYuan path-traversal bypass via Windows extended-length prefix](https://junglewise.ai/threats/cve-2026-116171-siyuan-3-5-4-before-3-8-7-on-windows-contains-a-sensitive-path)
- [SiYuan stored cross-site scripting in KaTeX math blocks](https://junglewise.ai/threats/cve-2026-116169-siyuan-from-2-10-0-before-3-8-7-contains-a-stored-cross-site)
- [SiYuan path traversal in MCP asset tool via incomplete blacklist](https://junglewise.ai/threats/cve-2026-116168-siyuan-before-3-8-7-contains-a-path-traversal-vulnerability-in)
- [SiYuan getAttributeViewSearchTarget insufficient access control](https://junglewise.ai/threats/go-2026-6632-siyuan-getattributeviewsearchtarget-returns-database-row-fd3e0f1a)
- [SiYuan Cross-Site WebSocket Hijacking in network proxy endpoint](https://junglewise.ai/threats/cve-2026-74802-siyuan-cross-site-websocket-hijacking-on-the-admin-only-network)