Dropbear home page http://matt.ucc.asn.au/dropbear/dropbear.html
"Security update 2012.55 — releases from 0.52 to 2011.54 are potentially vulnerable to code execution as root by an authenticated user if a command="..." option is used in authorized_keys. Release 2012.55 fixes the problem."
Debian stable (squeeze) is running Dropbear sshd v0.52. Debian testing (wheezy) includes Dropbear sshd v2012.55
Luckily, you can install Dropbear sshd v2012.55 from the testing repo on your stable system without breaking anything.
Short version 1) Add testing to your /etc/apt/sources.list 2) Create an /etc/apt/preferences file that tells apt the priority order for version control between stable, testing, unsable. 3) apt-get update 4) apt-get install dropbear/testing
Long version Read and learn :) http://jaqque.sbih.org/kplug/apt-pinning.html
Have fun and stay safe kids!
Credits go to John H. Robinson, IV jaqque@debian.org for the doc on apt pinning.
