I believe I have found the culprit. A few days ago I initialized an open proxy with the SSH Daemon, and about the same time this started happening. Here are the only other records in my log files in that time period plus or minus 3 minutes.
Code:
/var/log/auth.log.1:Oct 8 02:40:58 www sshd[2411]: error: connect_to 168.95.5.32 port 25: failed.
/var/log/auth.log.1:Oct 8 02:40:58 www sshd[2411]: error: connect_to 168.95.5.11 port 25: failed.
/var/log/auth.log.1:Oct 8 02:40:58 www sshd[2411]: error: connect_to 176.9.24.80 port 25: failed.
/var/log/mail.info.1:Oct 8 02:40:58 www postfix/smtpd[13935]: B86FE681: client=www[127.0.0.1]
/var/log/mail.log.1:Oct 8 02:40:58 www postfix/smtpd[13935]: B86FE681: client=www[127.0.0.1]
