Very likely not as bad. "Shellshock" is a bad flaw, but unless you have a terribly botched Linux system, it should work fine. The worst scenario that I can find there is sneaking some code into all shell scripts executed by root.
As best I understand, it allows statements after a bash environment variable declaration to be executed as root, without superuser access?
Maybe something like installing a package from an unchecked repo, which contains a shell script that runs something nasty like rm -rf /* (or something more subtle if the hacker isnt just an annoying troll).
Im not sure how this could affect a server, since I dont know much about how networking works, but wouldnt a potential hacker need login info to even start communicating remotely with a server through ssh or the like?
Rather disturbing news though.