Speculating on Speculative Execution

Threat actors continue to design exploits that specifically target physical weaknesses in processor hardware rather than more traditional software vulnerabilities. The now infamous attacks, Spector and Meltdown, ushered in a new era of hardware-based security vulnerabilities that have caused some experts to question whether the potential cybersecurity risks associated with simultaneous multithreading (SMT), also known as hyperthreading (HT), are potent enough to outweigh its computational advantages. A small pool of researchers now touts the need to disable SMT completely. However, this appears to be an extreme reaction; while a more security focused environment might be inclined to disable SMT, environments with a greater level of risk tolerance that may need the performance advantages offered by SMT to facilitate business operations, should not disable it by default and instead evaluate software application-based patch mitigations. This paper provides insights that can help make informed decisions when determining the suitability of SMT by exploring key processes related to multithreading, reviewing the most common exploits, and describing why Spectre and Meltdown do not necessarily warrant disabling HT.

@article{Dinerman2019,
  title     = {Speculating on Speculative Execution},
  journal   = {International Journal of Advanced Computer Science and Applications},
  volume    = {10},
  number    = {10},
  year      = {2019},
  publisher = {The Science and Information Organization},
  author    = {Jefferson Dinerman},
  doi       = {10.14569/IJACSA.2019.0101053},
  url       = {https://doi.org/10.14569/IJACSA.2019.0101053}
}