CVE-2026-54069CWE-346

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

Critical · published June 24, 2026

CVSS v4.0
9.2
EPSS
1%
Percentile
46.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
9.2 · CRITICAL
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
EPSS
0.00579 · 46.9th percentile
Weakness
CWE-346 · Origin Validation Error
Published
2026-06-24T21:17Z
EPSS history
Timeline
  • 24 JUN 21:17Z
    SiYuan: Unauthenticated Admin API Access via Blanket chrome-extension:// Origin Allowlist
    cvelistv5