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

Source

https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-54069.yaml

Associated Vulnerability

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

Description

SiYuan Note 3.6.5 and prior is vulnerable to authentication bypass. The CheckAuth middleware unconditionally trusted all chrome-extension:// origins, granting RoleAdministrator access without token validation to any request with a spoofed Origin header. Fixed in v3.7.0.

File Snapshot

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