CVE-2026-73046

SiYuan before v3.7.4 improperly restricts excessive authentication attempts in the CheckAuth() middleware. The HTTP Basic Authentication branch, which guards nearly the entire /api/* surface, accepts the workspace access code (Conf.AccessAuthCode) as the Basic Auth password but never consults the CAPTCHA/lockout gate or increments the failure counter used by the cookie/session login path. This allows unauthenticated remote attackers to brute-force the admin access code with unlimited automated requests and obtain full RoleAdministrator access to the kernel. A secondary weakness exists because the access code is compared using a non-constant-time string comparison.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3xh-mmmh-r54v
https://www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-http-basic-auth
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3xh-mmmh-r54v

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 22:16

Updated : 2026-08-26 17:05

NVD link : CVE-2026-73046

Mitre link : CVE-2026-73046

CVE.ORG link : CVE-2026-73046

JSON object : View

Products Affected

No product.

CWE

CWE-307

Improper Restriction of Excessive Authentication Attempts

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