The remote host is missing an update to proftpd-dfsg announced via advisory DSA 2191-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202191-1

Several vulnerabilities have been discovered in ProFTPD, a versatile, virtual-hosting FTP daemon: CVE-2008-7265 Incorrect handling of the ABOR command could lead to denial of service through elevated CPU consumption. CVE-2010-3867 Several directory traversal vulnerabilities have been discovered in the mod_site_misc module. CVE-2010-4562 A SQL injection vulnerability was discovered in the mod_sql module. For the oldstable distribution (lenny), this problem has been fixed in version 1.3.1-17lenny6. The stable distribution (squeeze) and the unstable distribution (sid) are not affected, these vulnerabilities have been fixed prior to the release of Debian 6.0 (squeeze). We recommend that you upgrade your proftpd-dfsg packages.