Security flaw in BASH. Remember to update your system !
Information recovery by Gambit on the francophone Forum, the Bash shell has a flaw (shellsock) allow the execution of malicious scripts.
So think to quickly update your servers (not that Raspberry elsewhere) :
apt-get update && apt-get upgrade -y
This could avoid you surprises
More information about the fault : https://www.debian.org/security/2014/dsa-3035