Sendmail Trojan Looks Familiar
The sophisticated backdoor came to light Tuesday through an advisory from the government-funded Computer Emergency Response Team (CERT) Coordination Center. CERT warned that copies of version 8.12.6 of Sendmail downloaded between September 28th and October 6th from the Sendmail Consortium's public FTP server contained the backdoor.
Once downloaded, the victim unwittingly activates the backdoor by compiling Sendmail from source code. The malicious code then establishes a secret control channel to a particular Internet host over TCP port 6667, according to the CERT advisory.