Nginx Proxy Manager through 2.16.0 lacks rate-limiting on authentication endpoints, allowing unauthenticated attackers to make unlimited password guesses against any account. Attackers can brute-force login credentials via POST /api/tokens and subsequently guess TOTP codes via POST /api/tokens/2fa to gain full session access and administrative control.
Weakness
The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.
Potential Mitigations
Common protection mechanisms include:
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
Consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator. [REF-45]
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/16.html
- https://cwe.mitre.org/data/definitions/49.html
- https://cwe.mitre.org/data/definitions/560.html
- https://cwe.mitre.org/data/definitions/565.html
- https://cwe.mitre.org/data/definitions/600.html
- https://cwe.mitre.org/data/definitions/652.html
- https://cwe.mitre.org/data/definitions/653.html
References
- https://github.com/NginxProxyManager/nginx-proxy-manager
- https://github.com/NginxProxyManager/nginx-proxy-manager/blob/v2.16.0/backend/app.js#L15-L58
- https://github.com/NginxProxyManager/nginx-proxy-manager/blob/v2.16.0/backend/internal/2fa.js#L196-L240
- https://github.com/NginxProxyManager/nginx-proxy-manager/blob/v2.16.0/backend/internal/token.js#L154-L182
- https://github.com/NginxProxyManager/nginx-proxy-manager/pull/5908
- https://www.vulncheck.com/advisories/nginx-proxy-manager-through-2.16.0-missing-brute-force-protection