spectre

Definition

A class of CPU vulnerabilities disclosed in 2018 that abuse speculative execution: the processor runs instructions ahead of a resolved branch, and although the architectural results are discarded, their effect on the cache persists and can be recovered through timing. Spectre is hard to eliminate because it stems from a performance mechanism built into the architecture rather than a coding bug, so mitigations generally cost throughput. It affected a broader range of processors than the contemporaneous Meltdown.

Explainers using this term

• CPU Pipelines and Branch Prediction — The Factory Inside One Clock TickSpectre Attacks: Exploiting Speculative Execution