A serious vulnerability that remains unfixed in many Android devices is under active exploit, marking the first known time real-world attackers have used it to bypass key security protections built in to the mobile operating system.
Dirty Cow, as the vulnerability has been dubbed, came to light last October after lurking in the kernel of the Linux operating system for nine years. While it amounts to a mere privilege-escalation bug—as opposed to a more critical code-execution flaw—several characteristics make it particularly potent. For one, the vulnerability is located in a part of the Linux kernel that’s almost universally available. And for another, reliable exploits are relatively easy to develop.
By the time it was disclosed, it was already under active exploit on Linux servers. Within days of its disclosure, researchers and hobbyists were using the vulnerability, indexed as CVE-2016-5195, to root Android phones.