OpenSSH protects against the following threats to network security:
IP spoofing
In the event of IP spoofing a remote computer sends packets with a counterfeited sender address. OpenSSH even provides protection against a spoofer in the local network who claims to be your router for outgoing messages.
DNS spoofing
In the event of DNS spoofing an attacker falsifies the Resource Records (RR) in the DNS Name Server.
Connection hijacking
Eavesdropping
Unauthorized tapping into unencrypted passwords and other plaintext messages.
Data corruption
OpenSSH protects against unauthorized reading and data corruption by encrypting the network traffic. OpenSSH prevents IP spoofing and DNS spoofing by authenticating the communication partners.
Thus an attacker who has obtained control over the network can only force the disconnection of OpenSSH. However, the attacker cannot
decrypt messages,
intercept messages and read them in again,
engage in connection hijacking.