Vulnerability · Published Jun 24, 2026 · Assigned by GitHub_M

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

Critical 9.2

In plain English

A critical-severity security flaw in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 7.5% (higher than 94% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei. Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)9.2Critical

Exploit odds (30 days)7.5%top 5.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack tooling1Nuclei

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/siyuan-note/siyuan/kernel	0.0.0-20260628153353-2d5d72223df4	GHSA-hvr9-72v2-fff3
Go	github.com/siyuan-note/siyuan/kernel	0.0.0-20260628153353-2d5d72223df4	GO-2026-5961

Affected products (as reported)

Vendor	Product	Versions
siyuan-note	siyuan	< 3.7.0

Weakness: CWE-346 · 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

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-hvr9-72v2-fff3 x_refsource_CONFIRM