Linux users, listen up! The Debian site was compromised a little while back due to an exposure in the kernel. Secunia has issued this security advisory but it’s very recent (as in, dated December 2) against kernels older than 2.4.23. Gentoo, SuSE, Mandrake, Red Hat, Slackware — as near as I can tell, all of the Linux “vendors” have the problem and are addressing it.
You should also update your rsync package while you’re at it.