2021/07/13 by Itzel Vázquez Sandoval, Arash Atashpendar, Sandoval, Itzel Vazquez +5
Computer Science · #Advanced Authentication Protocols Security #Cryptography and Security (cs.CR) #FOS: Computer and information sciences #User Authentication and Security Systems
paper · pdf · doi:10.48550/arxiv.2107.06090
openalex publication_date 2021/07/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose the use of PAKE for achieving and enhancing entity authentication\n(EA) and key management (KM) in the context of decentralized end-to-end\nencrypted email and secure messaging, i.e., where neither a public key\ninfrastructure nor trusted third parties are used. This approach not only\nsimplifies the EA process by requiring users to share only a low-entropy\nsecret, e.g., a memorable word, but it also allows us to establish a\nhigh-entropy secret key; this key enables a series of cryptographic\nenhancements and security properties, which are hard to achieve using\nout-of-band (OOB) authentication. We first study a few vulnerabilities in\nvoice-based OOB authentication, in particular a combinatorial attack against\nlazy users, which we analyze in the context of a secure email solution. We then\npropose tackling public key authentication by solving the problem of "secure\nequality test" using PAKE, and discuss various protocols and their properties.\nThis method enables the automation of important KM tasks (e.g. key renewal and\nfuture key pair authentications), reduces the impact of human errors, and lends\nitself to the asynchronous nature of email and modern messaging. It also\nprovides cryptographic enhancements including multi-device synchronization and\nsecure secret storage/retrieval, and paves the path for forward secrecy,\ndeniability and post-quantum security. We also discuss the use of auditable\nPAKEs for mitigating a class of online guess and abort attacks in\nauthentication protocols. To demonstrate the feasibility of our proposal, we\npresent PakeMail, an implementation of the core idea, and discuss some of its\ncryptographic details, implemented features and efficiency aspects. We conclude\nwith some design and security considerations, followed by future lines of work.\n