The remote host is missing an update to kernel-image-2.4.17-ia64 announced via advisory DSA 444-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20444-1

Paul Starzetz and Wojciech Purczynski of isec.pl discovered a critical security vulnerability in the memory management code of Linux inside the mremap(2) system call. Due to missing function return value check of internal functions a local attacker can gain root privileges. For the stable distribution (woody) this problem has been fixed in version 011226.16 of ia64 kernel source and images. Other architectures are or will be mentioned in a separate advisory respectively or are not affected (m68k). For the unstable distribution (sid) this problem will be fixed in version 2.4.24-3. This problem is also fixed in the upstream version of Linux 2.4.25 and 2.6.3. We recommend that you upgrade your Linux kernel packages immediately.