hi cole,

if implemetable you couldd use naxsi https://github.com/nbs-system/naxsi
for this, there exists a rule to detect and block shellshock-exploit-attempts:

MainRule "str:() {" "msg:Possible Remote code execution through Bash CVE-2014-6271" "mz:BODY|HEADERS" "s:$ATTACK:8" id:42000393 ;

see -> http://spike.nginx-goodies.com/rules/view/42000393

there is also an extended ruleset available
-> https://bitbucket.org/lazy_dogtown/doxi-rules



cheers,

mex