We describe Swivel, a new compiler framework for hardening WebAssembly (Wasm) against Spectre attacks. Outside the browser, Wasm has become a popular lightweight, in-process sandbox and is, for example, used in production to isolate different clients on edge clouds and function-as-a-service platforms. Unfortunately, Spectre attacks can bypass Wasm's isolation guarantees. Swivel hardens Wasm against this class of attacks by ensuring that potentially malicious code can neither use Spectre attacks to break out of the Wasm sandbox nor coerce victim code—another Wasm client or the embedding process—to leak secret data.
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SpectreGuard: An Efficient Data-centric Defense Mechanism against Spectre Attacks
Speculative execution is an essential performance enhancing technique in modern processors, but it has been shown to be insecure. In this paper, we propose SpectreGuard, a novel defense mechanism against Spectre attacks. In our approach, sensitive memory blocks (e.g., secret keys) are marked using simple OS/library API, which are then selectively protected by hardware from Spectre attacks via low-cost micro-architecture extension. This technique allows microprocessors to maintain high performance, while restoring the control to software developers to make security and performance trade-offs.
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- Award ID(s):
- 1718880
- NSF-PAR ID:
- 10097437
- Date Published:
- Journal Name:
- Design Automation Conference
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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