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Title: Compositional security for reentrant applications
The disastrous vulnerabilities in smart contracts sharply remind us of our ignorance: we do not know how to write code that is secure in composition with malicious code. Information flow control has long been proposed as a way to achieve compositional security, offering strong guarantees even when combining software from different trust domains. Unfortunately, this appealing story breaks down in the presence of reentrancy attacks. We formalize a general definition of reentrancy and introduce a security condition that allows software modules like smart contracts to protect their key invariants while retaining the expressive power of safe forms of reentrancy. We present a security type system that provably enforces secure information flow; in conjunction with run-time mechanisms, it enforces secure reentrancy even in the presence of unknown code; and it helps locate and correct recent high-profile vulnerabilities.  more » « less
Award ID(s):
1704788
NSF-PAR ID:
10233391
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the IEEE Symposium on Security and Privacy
ISSN:
1063-9578
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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