Protocol insecurity with finitely many sessions and XOR

R Ramanujam; Vaishnavi Sundararajan; S P Suresh

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arXiv · 2506.24072

Protocol insecurity with finitely many sessions and XOR

R Ramanujam·Vaishnavi Sundararajan·S P Suresh

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Abstract

We present a different proof of the insecurity problem for XOR, solved in by Chevalier, Kuesters, Rusinowitch and Turuani (2005). Our proof uses the notion of typed terms and well-typed proofs, and removes a restriction on the class of protocols to which the [CKRT05] proof applies, by introducing a slightly different (but very natural) notion of protocols, where honest agent sends are derivable from previous receives in the same session.

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R Ramanujam, Vaishnavi Sundararajan, S P Suresh. 2025-06-30. Protocol insecurity with finitely many sessions and XOR. https://arxiv.org/abs/2506.24072

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