Backports.org has released a port of Kernel 2.4.24 for Debian GNU/Linux 3.0

Kernel images and source packages for 2.4.24 are available, which fixes the mremap() local root vulnerability.

Here the apt sources:

# Kernel 2.4.24
deb http://www.backports.org/debian stable kernel-image-2.4.24-i386
deb-src http://www.backports.org/debian stable kernel-image-2.4.24-i386
deb http://www.backports.org/debian stable kernel-source-2.4.24
deb-src http://www.backports.org/debian stable kernel-source-2.4.24