Hitting the web on Friday afternoon was the Linux
2.6.20.15 and
2.6.21.6 kernels. The Linux 2.6.20.15 and 2.6.21.6 kernels fix a security problem with netfilter messages and Greg KH strongly urges all Linux 2.6.20 and 2.6.21 users that rely upon netfilter to upgrade to this latest version.