Using ssh: Do security risks outweigh the benefits?

Abstract

The secure shell (ssh) protocol encrypts network traffic, supports several types of authentication, and X11 connection forwarding, offers bi-directional port translation over encrypted channels, and counters session hijacking and other potentially catastrophic types of attacks. This protocol is so widely used today that many IT professionals, especially IT information security professionals, assume that there are almost no downsides from a security perspective. This is far from the case, however. Not only does ssh give system administrators and users a false sense of security, but numerous implementations of the ssh protocol (particularly the OpenSSH implementation) have had literally scores of vulnerabilities that need to be fixed. The Secure Shell (ssh) protocol is anything but secure. Systems administrators need to weigh the risks and costs of a compromised system against the convenience and costs of mitigating those risks when using ssh.