A major flaw in the Linux Bash feature was discovered on September 24. This vulnerability, known as Shellshock, could allow hackers to execute shell commands without any restriction from the environment. This bug makes it possible for hackers to take control of the data and programs of affected computers.

The "Bourne-Again shell" or "Bash" is the default interface system (shell) of Ubuntu. It evaluates the environment variables from a foreign environment.

The Shellshock security flaw is significantly important because the use of Bash is widespread. Indeed, it affects all Linux distributions, including OS X from Apple.

Here the affected systems:

  1. Ubuntu
  2. CentOS
  3. Debian
  4. Mac OS

Fortunately, security experts estimate that Shellshock is relatively easy to correct. The problem lies mainly in the difficulty of identifying the number of vulnerable devices.