Nagios Fusion versions prior to 2024R2.1 contain a brute-force bypass in the Two-Factor Authentication (2FA) implementation. The application did not properly enforce rate limiting or account lockout for repeated failed 2FA verification attempts, allowing a remote attacker to repeatedly try second-factor codes for a targeted account. By abusing the lack of enforcement, an attacker could eventually successfully authenticate to accounts protected by 2FA.
The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.
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]