The remote host is missing an update to sendmail announced via advisory DSA 1015-1. Mark Dowd discovered a flaw in the handling of asynchronous signals in sendmail, a powerful, efficient, and scalable mail transport agent. This allows a remote attacker may to exploit a race condition to execute arbitrary code as root. For the old stable distribution (woody) this problem has been fixed in version 8.12.3-7.2.
For the stable distribution (sarge) this problem has been fixed in version 8.13.4-3sarge1. For the unstable distribution (sid) this problem has been fixed in version 8.13.6-1. We recommend that you upgrade your sendmail package immediately. https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201015-1