The remote host is missing an update to moxftp announced via advisory DSA 281-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20281-1

Knud Erik Højgaard discovered a vulnerability in moxftp (and xftp respectively), an Athena X interface to FTP. Insufficient bounds checking could lead to execution of arbitrary code, provided by a malicious FTP server. Erik Tews fixed this. For the stable distribution (woody) this problem has been fixed in version 2.2-18.1. For the old stable distribution (potato) this problem has been fixed in version 2.2-13.1. For the unstable distribution (sid) this problem has been fixed in version 2.2-18.20. We recommend that you upgrade your xftp package.