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Speculative execution attacks leverage the speculative and out-of-order execution features in modern computer processors to access secret data or execute code that should not be executed. Secret information can then be leaked through a covert channel. While software patches can be installed for mitigation on existing hardware, these solutions can incur big performance overhead. Hardware mitigation is being studied extensively by the computer architecture community. It has the benefit of preserving software compatibility and the potential for much smaller performance overhead than software solutions. This paper presents a systematization of the hardware defenses against speculative execution attacks that have been proposed. We show that speculative execution attacks consist of 6 critical attack steps. We propose defense strategies, each of which prevents a critical attack step from happening, thus preventing the attack from succeeding. We then summarize 20 hardware defenses and overhead-reducing features that have been proposed. We show that each defense proposed can be classified under one of our defense strategies, which also explains why it can thwart the attack from succeeding. We discuss the scope of the defenses, their performance overhead, and the security-performance trade-offs that can be made.
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The Technological Arms Race in Hardware Security
For many years there has been an arms race between designers and adversaries of secure hardware. Improvements in the strategies for attack spur new defense techniques, and better defenses lead to improved attacks. In this contribution, first, we examine the technological dimensions of this arms race. While defenders benefit from increased circuit density and decreasing feature size, attackers benefit from novel side-channel attack vectors based on optical and electromagnetic interactions with their target. Second, we analyze the feasibility and applicability of various side-channel attacks on primary units of cryptographic hardware. We also discuss the required time, cost, and expertise to mount these attacks. We then examine how well modern defense methods are capable of thwarting modern attack methods.
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- Award ID(s):
- 2219810
- PAR ID:
- 10421547
- Date Published:
- Journal Name:
- 2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)
- Page Range / eLocation ID:
- 303 to 308
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/EMCSI39492.2022.9889394
