An unknown number of devices may contain the Bash flaw, including millions of Web servers, Unix and Mac OS X systems. Bash is a Unix shell, meaning it’s an interpreter that allows you to orchestrate commands on Unix and Linux systems. By gaining shell, attackers could dump all data stored on a server, reconfigure the environment or unleash automated worms. Bash, however, has been around since 1989, and all but the most recent versions are potentially exploitable, and may also be present in outdated, unsupported software.”]
Source: https://www.govinfosecurity.com/bash-bug-bigger-than-heartbleed-a-7359