CVE-2026-73046
criticalpriority · track · 0EPSS 0.008 · 56 %ileEUEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3xh-mmmh-r54vcnnvd
- https://www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-http-basic-authcnnvd
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3xh-mmmh-r54venisa_euvd
- https://www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-http-basic-authenisa_euvd
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3xh-mmmh-r54vnvd
- https://www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-http-basic-authnvd
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