The remote host is missing an update to sup announced via advisory DSA 521-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20521-1

jaguar@felinemenace.org discovered a format string vulnerability in sup, a set of programs to synchronize collections of files across a number of machines, whereby a remote attacker could potentially cause arbitrary code to be executed with the privileges of the supfilesrv process (this process does not run automatically by default). CVE-2004-0451: format string vulnerabilities in sup via syslog(3) in logquit, logerr, loginfo functions For the current stable distribution (woody), this problem has been fixed in version 1.8-8woody2. For the unstable distribution (sid), this problem will be fixed soon. We recommend that you update your sup package.