CVE-2026-73046
CRITICALCVE-2026-73046 is a critical-severity (CVSS 9.8) CWE-307 vulnerability. O3 Security confirms whether CVE-2026-73046 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
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/*…
Description
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-73046 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-73046 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-73046. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-73046 in your dependencies?
O3 detects CVE-2026-73046 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.