It is a vulnerability in GNU’s bash shell, discovered in September of 2014, that gives attackers access to run
remote commands on a vulnerable system. The malicious software can take control of an infected machine,
launch denial-of-service attacks to disrupt websites, and scan for other vulnerable devices (including routers).
Which of the following vulnerabilities is being described?

A.
Shellshock

B.
Rootshock

C.
Rootshell

D.
Shellbash

Explanation:
Shellshock, also known as Bashdoor, is a family of security bugs in the widely used Unix Bash shell, the first of
which was disclosed on 24 September 2014.
https://en.wikipedia.org/wiki/Shellshock_(software_bug)