The remote host is missing an update to proftpd announced via advisory DSA 1218-1. It was discovered that the proftpd FTP daemon performs insufficient validation of FTP command buffer size limits, which may lead to denial of service.

For the stable distribution (sarge) this problem has been fixed in version 1.2.10-15sarge2. For the unstable distribution (sid) this problem has been fixed in version 1.3.0-13 of the proftpd-dfsg package. We recommend that you upgrade your proftpd package. https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201218-1