cryptography

TL;DR: This article is a design exploration rather than a cryptographic proposal. It examines whether splitting encrypted files into independently stored fragments can reduce metadata leakage and make encrypted storage harder to analyze. The approach adds complexity and does not strengthen encryption itself. 1. The one-file-one-object problem When people talk about file encryption, they usually f…

An Ode to Alan Turing · June Solstice Game Jam Dash through enemies, break the cyphers, decode the city and its Fall! Play free in your browser, no download: https://lancefall.pages.dev Summary Built solo, from scratch, in 13 days for the jam. 100% vanilla TypeScript, 1,400+ automated tests. A real-time dash-combat bullet-hell where your only power is a momentum light-spear but your real weapon i…

This is a submission for the June Solstice Game Jam What I Built The Longest Night is a browser game about codes, daylight, and one impossible question. It's June 21 — the solstice — and you're the night-shift cryptanalyst at a remote listening station. Four encrypted transmissions arrived at noon. Command wants them broken before the sun goes down, and the sun is going down: an animated sky drai…

The Code Most People Never See Yeah,yeah i know more than 90% of the people reading this have heard of bitcoin. Everyone talks about Bitcoin's price. Few people talk about what makes it actually work. Under the hood, Bitcoin is a marvel of applied cryptography, distributed systems, and elegant scripting and you don't need to be a cryptographer to understand it. 01 Transactions How a transaction i…

The information exchanged by modern devices is typically protected by cryptographic techniques, approaches that convert readable data into scrambled, unreadable code that can only be deciphered by authorized parties or devices. To descramble encrypted data, devices or accounts need access to randomly generated cryptographic keys, unique, randomly generated sequences of binary code, letters or num…

Combining analog security IP and digital cryptographic IP for comprehensive defense. The post Agile Analog Collaborates with Xiphera for Post-Quantum Cryptography Challenge appeared first on Semiconductor Digest .

What exactly did DeepMind find? Could this discovery help solve longstanding mathematical mysteries? And what might it mean for cryptography, computing, and our understanding of mathematics itself? In this video, we explore the science behind the discovery, the role of artificial intelligence in modern research, and why mathematicians around the world are paying close attention. […]

Client-specific preprocessing PIR supports sublinear online private queries after a linear-time offline phase that prepares client-specific hints. The relevant lower bound is tight: any scheme with $S$ bits of client storage and online cost $T$ must satisfy $S \cdot T = \Omega(n)$. Most practical random-set schemes fall short by a $\kappa$ factor in client storage, while the known constant-factor…

Most developers learn a hard lesson at some point in their careers: just because data is encrypted doesn't mean it’s safe from tampering. It’s an easy trap to fall into. If an attacker doesn't have the secret key, they can't read the data. And if they can't read it, how could they possibly modify it to do something malicious? But cryptography is unforgiving, and it treats secrecy and integrity as…

This paper presents the first practical end-to-end fault injection attacks on the post-quantum signature scheme PERK, based on the MPC-in-the-Head paradigm and relies on GGM tree expansions for efficient randomness generation. While GGM trees reduce memory requirements, they introduce implementation-level deviations from the theoretical model. We show that these implementation choices fundamental…

Due to the complexity of modern cryptographic algorithms, especially in the area of Post-Quantum Cryptography (PQC), conceptualizing optimal hardware designs in relation to some target performance metric is increasingly time-consuming and error-prone, particularly when combined with the need for secure side-channel protection mechanisms. To solve this, Buschkowski et al. presented the HADES frame…

Satellite communication systems, as critical long-lifecycle infrastructure, face a dual security challenge in the coming decades: the threat of quantum computers and the operational rigidity of traditional Public Key Infrastructure (PKI). While migrating to Post-Quantum Cryptography (PQC) addresses the former, it fails to solve the inefficiency of certificate management, where in-orbit policy upd…

Rate Limiting Nullifier (RLN) is a privacy-preserving and decentralized spam-prevention mechanism for anonymous broadcast networks: each member can emit at most $r$ signals per epoch, and any violation reveals a secret that enables the member's stake to be slashed. The standard construction binds each membership to a single secret key $\mathsf{sk}_G$, so the unit of identity, the unit of authoriz…

Distributed shuffling is a core primitive underlying mix-nets, electronic voting, and, more recently, single secret leader election (SSLE) protocols for proof-of-stake blockchains. In these settings, a collection of resource-constrained parties jointly permutes a list of ciphertexts or commitments in order to conceal the correspondence between inputs and outputs. Existing security analyzes of suc…

We give a witness-finding cryptanalysis of Stickel-type key exchange schemes, which involve two-sided multiplication of $n \times n$ matrices over $\mathbb{F}_p$, where these matrices are drawn from public subspaces with a particular commuting structure. This analysis covers Stickel's original proposal, Shpilrain's polynomial extension of that scheme, Nager's algebraic extension of that schem…

In 2011, Grigoriev and Shpilrain proposed using tropical algebraic structures in cryptography. In recent years, numerous protocols based on tropical and related structures have been introduced, as well as many attacks on some of these protocols. This direction of research is now known as tropical cryptography. As a result of the efforts both to design secure schemes and to analyze their vulnerabi…

Fully homomorphic encryption (FHE) enables non-interactive secure transformer inference (NISTI). Due to the high cost of bootstrapping, conventional approaches typically choose parameters that support a large multiplicative depth to reduce bootstrapping frequency. However, larger depth directly increases ciphertext size, resulting in higher communication and computation overheads. In this paper…

Poseidon is one of the most widely deployed arithmetization-oriented cryptographic permutations and plays a central role in modern zero-knowledge proof systems. Although several algebraic attacks on reduced-round variants have been proposed, the security of the recommended parameter sets remains intact. A central difficulty in such attacks is controlling the degree growth of the polynomial repres…

TL;DR: This is not a cryptographic construction. It is a pragmatic engineering compromise for applications where encrypted storage is required but approximate alphabetical ordering is still useful. I sort encrypted strings using an external index: the sum of weighted Unicode code points for the first N characters with exponential positional weights, followed by quantization. Monotonicity is prese…

What happens when the bits of an RSA private key are heavily biased toward 0 instead of being randomly generated? The public key’s bits could be biased enough for us to detect these incorrectly generated keys in the wild. Together with Hanno Böck of the badkeys project, we found hundreds of unique keys that not only have this property, but can be quickly factored. We also found the bug that led t…