http://threatpost.com/major-bash-vulnerability-affects-linux-unix-mac-os-x
检测：
$ env x='(){:;}; echo vulnerable' bash -c "echo this is a test"
中招的显示:
vulnerable
this is a test
如果是没有问题，则是下面
$ env x='(){:;}; echo vulnerable' bash -c "echo this is a test" bash: warning: x: ignoring function definition attempt bash: error importing function definition for `x' this is a test