- Security researchers at the University of Toronto warn against the Rowhammer flaw
- Older GPUs seem to be vulnerable
- Nvidia urges users to update as soon as possible
Nvidia urges users to apply attenuations that he provided against the so-called hammer-row attacks after new research has confirmed their potential to cause compromise of serious and stealth level.
Rowhammer is a feat of vulnerability in dynamic RAM (DRAM), where access several times (or “marteler”), a row of memory can cause bits in the adjacent lines. Consequently, threat actors could bypass security limits, trigger privilege climbing, falsification of data or even service denial states.
Although it is a hardware level problem, software -based techniques can trigger and arm the flaw remotely.
More recent GPUs are safe
Although known for more than a decade, Rowhammer’s attacks were first exploited in 2018, and even – very rarely and in limited capacity – mainly because of their complexity and their material dependencies.
However, the security researchers Chris (Shaopng) Lin, Joyce Qu and Gururaj Savezhwar, of the University of Toronto recently published new research demonstrating the practical use of the fault:
“We ran Gpuhammer on an NVIDIA RTX A6000 (48 GB GDDR6) on four DRAM banks and observed 8 distinct flips with a single bit, and bits flips in all the banks tested,” the researchers said. “The number of minimum activation (TRH) to induce a flip was ~ 12K, in accordance with the previous results of DDR4.”
“Using these Flips, we made the first ML accuracy degradation attack using Rowhammer on a GPU.”
The ML accuracy degradation attack means that Rowhammer has been used to degrade the accuracy of the automatic learning model, from 80% usual to 1% depressing, using a single flip bits.
NVIDIA has urged users to activate the error correction code at the system level, which protects against Rowhammer on GDDR6 devices. The attenuation works by adding redundant bits and correcting bits errors, maintaining the reliability and precision of the data.
The list of affected GPUs is quite extensive, and in addition to the RTX A6000, includes several Blackwell, Volta and Turing products.
The full list can be found on this link – but more recent GPUs are delivered with integrated protection, said Nvidia.
Via Bleeping Compompute
