'Dirty Cow' Linux vulnerability found after nine years

The 'Dirty Cow' bug was originally introduced nine years ago, and has been sitting unnoticed for much of that time

The operating system that lies at the core of most servers on the internet and most smartphones has a critical vulnerability which has existed, unnoticed, for nine years.

Called "Dirty Cow" (because it exploits a mechanism called copy-on-write), the bug allows an attacker to gain privilege escalation on the Linux kernel.