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What is a Telnet vulnerability?

By Corvus Threat Intel & Risk Advisory
1 minute
Last Updated October 28, 2020

Telnet overview

Publicly available Telnet service can leave your clients vulnerable to data leaks of information like usernames and passwords. Because Telnet is one of the earliest remote login protocols on the Internet, initially released in 1969, it provides no built-in security measures and suffers from serious security issues. The use of Telnet over the public Internet should be avoided due to the risk of exposing usernames and passwords to the attacker and increasing the likelihood of exploitation.

Telnet is an early application protocol, the presence of which triggers an alert from Corvus when identified on a policyholder’s IT system. Click here to learn about dynamic security alerts.

Best practices to help your clients in securing Telnet vulnerabilities

Replacing insecure Telnet with Secure Shell (SSH) is the ideal resolution. We recommend that your clients take the following steps to address their Telnet vulnerability.

  1. Work with their IT team to investigate the vulnerability
  2. Implement SSH (Secure Shell) as a secure alternative to Telnet
    • Corvus is also here to answer questions about how to resolve an issue

Learn more about Telnet and implementing SSH

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