DIGITAL LIFE

Hacker shows how a cigarette lighter can grant you root access

Security researchers are always looking for innovative ways to exploit systems, and a blogger's latest technique takes it to a shockingly low-tech level. David Buchanan, a well-known hardware modder, has detailed how he was able to gain root access on a laptop using nothing more than a resistor, wire, some tinkering, and a plain old cigarette lighter.

Buchanan walks through his process of experimenting with low-cost fault-injection attacks as an alternative when typical software bugs aren't available to exploit.

"Before you can write an exploit, you need a bug. When there are no bugs, we have to get creative – that's where fault injection comes in," he explains.

The method involves a hard DRAM mod, soldering a tiny 15-ohm resistor, and wiring an "antenna" to specific pins on the laptop's memory module. He also strategically loaded the system's memory with exploitable page tables to increase his chances of a successful hack and corrupt the memory address mappings.

With a few extra steps, Buchanan managed to configure the machine to grant root privileges, letting him read/write to any point in the physical memory. All he had to do to gain access was spark up a regular piezo-electric lighter near this antenna, which would induce targeted bitflip errors in the machine's memory.

The method's success rate isn't exactly 100%, with Buchanan noting that it usually "takes several clicks of the lighter to get a good glitch." Nonetheless, the demo is still an eye-opening demonstration of the scope of electromagnetic fault injection attacks.

Before you start worrying about cybercriminals breaking into systems by waving Bics around, it's important to note that for this attack to work, you'd need unrestricted physical access to the target device and a ton of time to properly configure the memory hardware mod. The likelihood of this technique being used in the wild is extremely low.

However, as Buchanan explains, it could potentially allow you to jailbreak or unlock hardware you already own, like circumventing digital rights management on game consoles and media players.

Buchanan also hinted in his blog at potential future endeavors, like perhaps finding similarly clever hardware hacks for upcoming devices such as the Nintendo Switch 2, which he says is what motivated him.

That said, if this little hack impressed you, you'll also be delighted by this previous hack where Buchanan was able to cram the entire works of Shakespeare into a tiny image and post it in a tweet.

mundophone