Improper Certificate Validation
An issue was discovered in MikroTik RouterOS 6.41.4. Missing OpenVPN server certificate verification allows a remote unauthenticated attacker capable of intercepting client traffic to act as a malicious OpenVPN server. This may allow the attacker to gain access to the client's internal network (for example, at site-to-site tunnels).
CWE-295 - Improper Certificate Validation
The authenticity component of a web system stems from the ability to validate “Digital certificates”, which (i) establish trust between two or more entities sharing data over a network; (ii) ensure data at rest and transit is secure from unauthorized access; and (iii) check the identity of the actors that interact with the system. An application with absent or ineffective certificate validation mechanisms allows malicious users, impersonating trusted hosts, to manipulate the communication path between the client and the host, resulting in unauthorized access to data and to the application’s internal environment, and potentially enabling man-in-the-middle attacks.