New Hertzbleed Side Channel Attack Affects All Modern AMD and Intel CPUs
Jun 15, 2022
A newly discovered security vulnerability in modern Intel and AMD processors could let remote attackers steal encryption keys via a power side channel attack. Dubbed Hertzbleed by a group of researchers from the University of Texas, the University of Illinois Urbana-Champaign, and the University of Washington, the issue is rooted in dynamic voltage and frequency scaling ( DVFS ), a power and thermal management feature employed to conserve power and reduce the amount of heat generated by a chip. "The cause is that, under certain circumstances, periodic CPU frequency adjustments depend on the current CPU power consumption, and these adjustments directly translate to execution time differences (as 1 hertz = 1 cycle per second)," the researchers said. This can have significant security implications on cryptographic libraries even when implemented correctly as constant-time code to prevent timing-based side channels, effectively enabling an attacker to leverage t...