The Linux exploit called Rowhammer is back in the news. This time, it’s targeting Android devices.
If you missed the news about Rowhammer, or need a refresher, the exploit basically works like this: if you can engineer a piece of malware that will consistently access the same row of memory on an installed chip, hammering at it, it will cause electricity to leak to the adjacent row of memory, which is expressed as a bit. This bit is all that’s needed for a hacker to take full control of the target system.
Unfortunately, the Android operating system is based on Linux, and recently, researchers have demonstrated that the same basic kind of attack can be used to take root level control over Android devices.
This new proof of concept has been dubbed “Drammer” and could potentially impact most of the Andriod devices on the market today. The researchers started with Android devices because they were already familiar with Linux, but were quick to point out that the same type of attack could likely be engineered to work against devices running iOS with additional research.
If there was a severity level higher than “critical,” Rowhammer and Drammer would occupy that designation. It’s about as serious as a security flaw can get, because it requires no special permissions to run, and can even work when the user puts their smart device in sleep mode.
Worse, there’s no easy fix for this. The exploit that Drammer and Rowhammer rely on to work is so fundamental to OS design that it would require a dramatic overhaul and rethink to patch out of existence.
Fortunately, there have been no reported instances of this attack being used in the wild. For now, it exists solely as a proof of concept and is confined to the research lab. That said, it’s just a matter of time before a hacker of sufficient skill works out a reliable way to deploy malware containing this exploit, at which time, all bets are off.
