{"id":"CVE-2026-73046","title":"SiYuan before v3.7.4 improperly restricts excessive authentication attempts in the CheckAuth() middleware","summary":"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.Acces…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-307"],"published":"2026-08-15","updated":"2026-08-15","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-73046","references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3xh-mmmh-r54v","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-http-basic-auth","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"ingestedAt":"2026-08-16T13:39:04.280Z","epss":0.00425,"epssPercentile":0.36318,"slug":"CVE-2026-73046","body":"## Overview\n\nSiYuan 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}