Security experts have warned that a deadly bug named Shellshock is affecting hundreds of millions of computers, servers and devices.
The bug is reportedly much more fatal than Heartbleed, researchers say.
According to the BBC, the flaw has been found in a software component known as Bash, which is a part of many Linux systems as well as Apple's Mac operating system.
Researchers believe that the bug can be used to remotely take control of nearly all types of system with the help of Bash.
Prof Alan Woodward, a security researcher from the University of Surrey said that while Heartbleed was all about sniffing what was going on, the new bug was about giving one direct access to the system.
