Intel has released microcode and BIOS updates to address Plundervolt attack. Researchers demonstrated novel yet another technique to hijack Intel SGX, a trusted space on modern Intel CPUs that encrypts extremely sensitive data to shield it from attackers even when a system gets compromised. Intel is not aware of any of these issues being used in the wild, but as always, we recommend installing security updates as soon as possible. The attack relies on the fact that modern processors allow frequency and voltage to be adjusted when needed, which can be modified in a controlled way to induce errors in the memory by flipping bits.
Source: https://thehackernews.com/2019/12/intel-sgx-voltage-attack.html