The hottest Cryptography Substack posts right now

And their main takeaways
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Top Technology Topics

The Q-Day Edition

Why is this interesting? • 1025 implied HN points • 05 Feb 26
🕹 Technology Cryptography
  1. Nation-states are quietly collecting huge amounts of encrypted data today that they can’t read now, betting that future quantum computers will let them decrypt it later.
  2. That strategy flips the usual logic: instead of information losing value over time, encrypted data can become more valuable as quantum advances approach.
  3. This reality forces a rethink of security and policy — we need post-quantum encryption and stronger counterintelligence because many current secrets are effectively already compromised even if they remain unreadable today.

@adlrocha - We are Missing a Security Stack for Autonomous Agents

@adlrocha Weekly Newsletter • 129 implied HN points • 01 Feb 26
🕹 Technology Cryptography
  1. Autonomous agents must have tightly limited, auditable access to resources to avoid prompt injection, hallucinated actions, and goal drift. Ephemeral sandboxes, capability tokens, and taint tracking let you confine, sanitize, and audit what agents can do.
  2. Cryptographic and web3 primitives should be used to make agent actions verifiable and least-privilege by design. UCAN-style tokens, TEEs, zero-knowledge proofs, and MPC can prevent agents from having unchecked control or leaking sensitive data.
  3. Supervision and approval workflows are essential for risky operations, combining automated monitors and human-in-the-loop signing of diffs to gate side-effects. Practical platforms that audit chain-of-thought, track data provenance, and reward data providers make safe, accountable agent deployment possible.

Involutions: The License to Update in O(1)

Software Bits Newsletter • 206 implied HN points • 14 Jan 26
🕹 Technology Cryptography
  1. XOR is an involution: applying the same XOR twice cancels it out, so adding and removing an element use the same operation and let you update combined hashes in O(1).
  2. Zobrist hashing leverages XOR to update a chessboard hash with only a few XORs per move, enabling fast transposition-table lookups and huge search speedups; collisions are possible but usually acceptable or verifiable.
  3. More generally, pick the algebraic tool that matches your needs — use involutions like XOR for O(1) incremental updates when collisions are tolerable, rolling linear hashes for sliding windows, or Merkle trees when cryptographic integrity is required.

RISC-V and Post Quantum Cryptography

Fprox’s Substack • 186 implied HN points • 18 Jan 26
🕹 Technology Cryptography
  1. Quantum computers threaten today’s public-key cryptography, so governments and industry are already moving to post-quantum algorithms and rolling out standards and deployments now.
  2. Post-quantum schemes (e.g., Kyber, Dilithium, SPHINCS+, Falcon) rely on heavy math like NTT and Keccak, and they trade off key/signature sizes, signing speed, and verification cost differently.
  3. RISC-V can run PQC today using its vector extensions, but lacks dedicated PQC ISA support; targeted accelerations for NTT and Keccak (and vector crypto extensions) would greatly improve performance and are being explored by the community.

Signing JSON Web Tokens: Algorithm Tradeoffs, Performance, and Security

ciamweekly • 62 implied HN points • 09 Feb 26
🕹 Technology Cryptography
  1. Pick your JWT algorithm based on tradeoffs: HMAC (HS) is very fast and simple but uses a shared secret and cannot provide non-repudiation, while asymmetric algorithms let you separate signing and verification.
  2. Prefer modern asymmetric schemes when possible: RSA-PSS is safer than old PKCS#1 v1.5, ECDSA gives small fast signatures but demands perfect nonce randomness, and EdDSA (Ed25519) is usually the best choice because it’s fast, secure, and uses deterministic nonces.
  3. Match algorithm to your environment and tooling: RSA has the widest compatibility but large signatures and slower signing, ECDSA risks come from RNG mistakes, and EdDSA may require checking HSM/KMS and library support before committing.
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Under the microscope: Medal of Honor: Underground (PlayStation)

Rings of Saturn • 43 implied HN points • 18 Feb 26
🕹 Technology Cryptography
  1. The game doesn't store cheat passwords directly; it computes a CRC-32 checksum of whatever you type and compares that to a table of stored checksums to hide the real codes.
  2. Because CRC-32 updates can be reversed on a per-byte basis, a meet-in-the-middle attack that splits 10-letter codes into two 5-letter halves makes finding matching inputs feasible without brute forcing 26^10 combinations.
  3. Using that technique revealed many alternate valid strings and four previously unknown cheat effects (like No Reload and Unlimited Ammo), since many different 10-letter inputs map to the same 32-bit checksum.

New Nature

Breaking Smart • 105 implied HN points • 16 Jan 26
🕹 Technology Cryptography
  1. New Nature describes technologies that create durable, law-like regimes whose rules are nearly as persistent and inviolable as natural laws. This is mostly computation-based, so 'code is law' applies far beyond just blockchains.
  2. Some technologies can be capture-resistant or “can’t-be-evil,” like strong encryption, which shifts power toward weaker actors and helps prevent concentration of control, though physical or coordinated attacks still impose limits.
  3. Attempts to rely on wise human regulation tend to create attack surfaces that powerful actors can capture, so it’s preferable to build many widely distributed, capture-resistant systems rather than concentrate discretionary control.

Hashing Other Values

ciamweekly • 62 implied HN points • 26 Jan 26
🕹 Technology Cryptography
  1. Hash secrets that are created by your system, stored long-term elsewhere, high value, must stay secret, and are never needed in plaintext. Examples include MFA recovery codes, static API keys, and client secrets.
  2. Don’t hash values you must use in plaintext or that are public, because hashing either breaks functionality or is pointless; examples are private keys (used to sign) and public client identifiers.
  3. Hashing at rest is good defense-in-depth but not foolproof — short or simple secrets can be reversed with rainbow tables and hashed values must never be logged, so make secrets complex and rotate them if they get exposed.

The Unbreakable Message

Who is Robert Malone • 15 implied HN points • 28 Feb 26
🕹 Technology Cryptography
  1. Quantum communication uses quantum physics to make eavesdropping detectable, so intercepted messages can't be silently copied or later decrypted. This prevents the "harvest now, decrypt later" threat.
  2. Militaries, intelligence agencies, and banks are prioritizing quantum links for the most sensitive communications because the technology can provide a lasting strategic advantage. Whoever builds the networks and standards first could shape the global information architecture and force others to choose sides.
  3. Practical limits remain—photons are lost in fiber, quantum repeaters are needed, and current hardware is expensive and low-bandwidth—so broad consumer use is likely decades away. Once repeaters and miniaturization mature, a quantum internet and distributed quantum computing could reshape security, finance, healthcare, and science.

Password Storage

ciamweekly • 62 implied HN points • 12 Jan 26
🕹 Technology Cryptography
  1. Never store passwords in plain text or as reversible encrypted values; use a one-way password hashing algorithm (for example Argon2 or PBKDF2) chosen for your security and performance needs.
  2. Use a unique random salt per user and a tunable work factor (iterations/memory) that you increase over time as hardware improves, and consider adding a pepper stored separately for extra protection.
  3. Encrypt your database at rest as part of defense in depth, and remember hashed passwords are non-recoverable so you can verify passwords but not retrieve the plaintext.

@adlrocha - Is N=NP?

@adlrocha Weekly Newsletter • 64 implied HN points • 14 Dec 25
🕹 Technology Cryptography
  1. Complexity theory measures how much time and memory algorithms need so we can tell which problems scale feasibly and which become intractable. It separates problems that are merely computable from those that are practically solvable before resources run out.
  2. P contains problems solvable in polynomial time, while NP contains problems whose solutions can be verified quickly even if they seem hard to find. NP-Complete problems are the hardest in NP because every NP problem can be reduced to them, and NP-Hard problems are at least that hard but not necessarily verifiable quickly.
  3. If P = NP, many cryptographic systems would break because one-way functions would no longer exist. At the same time, P = NP would let us solve huge optimization and AI problems exactly and efficiently, radically changing many fields.

Under the microscope: LMA Manager 2003–2006 (PlayStation 2, Xbox)

Rings of Saturn • 43 implied HN points • 07 Jan 26
🕹 Technology Cryptography
  1. LMA Manager 2003–2005 use a custom obfuscation scheme to generate per-unique-ID bonus codes. That algorithm can be reimplemented so you can derive the codes from any Unique ID.
  2. LMA Manager 2006 uses RSA to validate codes, but the game's 64-bit modulus was trivial to factor, allowing recovery of the private key and recreation of valid codes. Reproducing the game's custom post-RSA processing (a modified Base32 and an XOR step) yields complete, working codes.
  3. Emulation, decompilation, and small scripts were used to extract the algorithms, and public generator scripts now produce all bonus codes, including an "all bonuses" code that unlocks everything.

Decentralized Cloud Computing

DeFi Education • 679 implied HN points • 31 May 22
🕹 Technology Cryptography
  1. Decentralized cloud computing is changing how we store and process data. It allows users to control their own data without relying on big companies.
  2. This approach can lead to better security and privacy for users. It’s often seen as a more trustable alternative to centralized systems.
  3. As the market for tokens is evolving, exploring decentralized projects can unveil exciting new opportunities in tech and finance. Staying informed can help you find the next big thing.

The Challenges and Benefits of Quantum Computing Security

Rod’s Blog • 39 implied HN points • 19 Feb 24
🕹 Technology Cryptography
  1. Quantum computing poses a serious threat to conventional cryptography due to powerful quantum algorithms like Shor's and Grover's, which can compromise commonly used encryption schemes.
  2. Preparing for quantum computing challenges now can lead to the development of quantum-resistant cryptography, using both classical and quantum techniques to withstand quantum attacks and enhance security.
  3. Quantum cryptography offers innovative possibilities like quantum key distribution and quantum secure communication, driving collaboration and innovation across various fields to enhance security and privacy.

How to Fake Decryption

Nonsense on Stilts • 1 HN point • 04 Sep 24
🕹 Technology Cryptography
  1. You can create a fake key and a fake message to trick someone into thinking they decrypted a message. This lets you mislead anyone watching your communication.
  2. It's important to plan what the fake message will be before sending the real one, so both parties know what to expect if asked.
  3. This technique could be used for serious purposes, like hiding important communications, or just for fun in games and stories.

Encryption bans are doomed

Nick Merrill • 58 implied HN points • 07 Jul 23
🕹 Technology Cryptography
  1. Steganography hides the fact that secret communication is occurring.
  2. Perfect steganography can make encryption bans impractical.
  3. Regulators may shift focus to controlling endpoints for monitoring content and speech.

The Future of Tech: Less-Hyped AI & Vibe Coding Out of Critical Systems?

ppdispatch • 8 implied HN points • 25 Nov 25
🕹 Technology Cryptography
  1. Linus Torvalds thinks vibe coding can be useful for learning but shouldn't be used for important software projects. It's a fun way for beginners to experiment, but it can lead to maintenance problems later.
  2. Cloudflare experienced a major outage that affected many popular services like X and OpenAI due to a faulty feature file. This highlights the fragility of web infrastructure and the need for robust systems.
  3. Google is tightening security for Android developers due to rising scams. They're making it easier for students and hobbyists to experiment while also ensuring that bad actors can't easily distribute harmful apps.

Number Theoretic Transform with RVV

Fprox’s Substack • 83 implied HN points • 07 Dec 24
🕹 Technology Cryptography
  1. The Number Theoretic Transform (NTT) helps speed up polynomial multiplication, which is important in cryptography. It uses a smart method to do complicated calculations faster than traditional methods.
  2. Using RISC-V Vector (RVV) technology can further improve the speed of NTT operations. This means that by using special hardware instructions, operations can be completed much quicker.
  3. Benchmarks show that a well-optimized NTT using RVV can be substantially faster than basic polynomial multiplication, making it crucial for applications in secure communications.

Faster NTT with RISC-V Vector

Fprox’s Substack • 62 implied HN points • 11 Jan 25
🕹 Technology Cryptography
  1. The Number Theoretic Transform (NTT) can speed up polynomial multiplications, which are important for modern cryptography. Optimizing how this process works leads to significant performance improvements.
  2. Using assembly language can help tailor code for specific hardware, allowing more direct control over how instructions are executed, which can greatly enhance speed.
  3. Combining multiple steps of the NTT process into fewer loops and minimizing unnecessary calculations can lead to much lower execution times, achieving targets that seemed difficult at first.

Quick Note: swapping pairs with RVV

Fprox’s Substack • 62 implied HN points • 25 Dec 24
🕹 Technology Cryptography
  1. There are two main techniques for swapping pairs of elements using RISC-V Vector: one uses slidedown and slideup operations, and the other uses narrowing and widening arithmetic. Each has its own method for rearranging elements.
  2. The slidedown and slideup technique tends to be faster because it uses fewer operations and avoids extra complexity, making it more efficient for swapping elements in practice.
  3. In testing, the slidedown method consistently showed lower latency in tasks compared to the widening approach, indicating it might be the better choice for optimizing performance in applications like NTT implementations.

Fostering Trust: Why NIST and the NSA Must Prioritise Transparency in Post-Quantum Cryptography.

Deep-Tech Newsletter • 19 implied HN points • 19 Oct 23
🕹 Technology Cryptography
  1. Post-Quantum Cryptography is crucial in securing digital communications against potential threats from quantum computers
  2. Enhancing transparency in standardization processes, inclusive collaboration, independent audits, and regular updates can build trust in cryptographic standards
  3. Collaboration between intelligence agencies and the private sector is vital for protecting critical infrastructure, fostering innovation, and addressing borderless cyber threats

TechLetters #124 - Generative-AI for ads approaching. Dwell time goes down.

Lukasz Olejnik on Cyber, Privacy and Tech Policy Critique • 19 implied HN points • 24 Apr 23
🕹 Technology Cryptography
  1. Google plans to use generative AI for dynamic ads, raising concerns about transparency and data protection.
  2. New cryptographic standards are compared to a jigsaw puzzle, emphasizing the complexity and precision required.
  3. The EU is establishing a 'cyber solidarity' reserve to address cybersecurity threats, with a focus on supporting countries like Ukraine.

Whale Songs Explained

David’s Substack • 19 implied HN points • 03 Oct 23
🕹 Technology Cryptography
  1. Whale Songs allows anonymous tweeting from accounts with $1M in on-chain assets
  2. Spartan-ECDSA is an important tool for zero-knowledge proof circuits
  3. Challenges include handling large datasets, computationally intensive processes, and server limitations

Newsletter #2: Certain Randomness

Decoding Coding • 19 implied HN points • 09 Feb 23
🕹 Technology Cryptography
  1. Random numbers are important in computer science for things like cryptography, simulations, and game mechanics. They help create unpredictability and realism in these applications.
  2. There are two main types of random number generators: True Random Number Generators (TRNGs) that use real-world entropy, and Pseudo Random Number Generators (PRNGs) that produce predictable outcomes based on a starting value.
  3. Algorithms like Linear Congruential Generators (LCGs) and Mersenne Twister are commonly used for generating pseudo-random numbers in various applications due to their efficiency and quality.

The Game of Diophantus

Thái | Hacker | Kỹ sư tin tặc • 1 HN point • 26 Jun 24
🔬 Science Cryptography
  1. Diophantus, an ancient Greek mathematician, is known for solving equations with two unknowns and his work formed the basis for modern cryptographic algorithms like ECC.
  2. The lost works of Diophantus, preserved during historical upheavals, resurfaced over centuries, impacting later mathematicians like Fermat, who posed the famous Last Theorem.
  3. The journey from Tycho, who pioneered data science with precise astronomical observations, to Kepler discovering that planetary orbits are ellipses, connects to the development of elliptic curves in mathematics.

Under the microscope: Skeleton Warriors (Saturn, PlayStation)

Rings of Saturn • 14 implied HN points • 08 Dec 24
🕹 Technology Cryptography
  1. The article talks about finding cheat codes for the game Skeleton Warriors on the Saturn and PlayStation consoles. It highlights how some of these codes were previously unknown and required research and coding to uncover.
  2. The author used a combination of brute force methods and mathematical approaches to determine the missing cheat codes. They collaborated with a cryptographer to solve complex hashing problems involved in the game.
  3. Mick West, a cofounder of Neversoft, contributed to the findings by sharing source code and insights about how the cheats work in the game. This shows a connection between game development and player discovery.

Non-Newtonian Computing?

Bzogramming • 30 implied HN points • 07 Jan 24
🕹 Technology Cryptography
  1. Physics has alternative framings like Lagrangian and Hamiltonian mechanics, which could inspire new ways of viewing computation.
  2. Reversible computing, preserving information by having bijective gates, is crucial for energy efficiency and future computing technologies.
  3. Studying constraint solvers and NP-complete problems can lead to insights for accelerating search algorithms and developing new computing approaches.

Lecture 09 Replay + LOGML 2022

Quantum Formalism • 19 implied HN points • 28 Jun 22
🚌 Education Cryptography
  1. The lecture 09 replay covering the application of cyclic groups and DLP in cryptography is available on YouTube.
  2. Future plans include a mini-course series on cryptography focusing on DLP cryptographic systems for security assurance.
  3. Joining the Discord Community is encouraged for organizing group study sessions and accessing live study session links.

[EVM: Zero to Hero] All About Accounts

Coinsights • 38 implied HN points • 22 Feb 23
🕹 Technology Cryptography
  1. EVM supports two types of accounts: Externally Owned Accounts (EOAs) and Contract Accounts (smart contracts)
  2. EOAs are controlled by private keys and can initiate transactions, while smart contracts run on code and cannot initiate transactions
  3. Smart Contract Wallets (SCWs) enhance wallet experience by utilizing the customizability of smart contracts

Want to help me upgrade digital identity?

Steve Kirsch's newsletter • 4 implied HN points • 01 Feb 25
🕹 Technology Cryptography
  1. Usernames and passwords are outdated. A new method of digital identity would make online security simpler and safer.
  2. You can manage your identity without needing to remember complicated passwords or codes. Just an alias is all you need.
  3. There’s a need for experts in cryptography and cloud security to help create a more secure and self-sovereign identity system.

Siêu trí tuệ: tìm số nguyên tố hay là tăng minh bạch cho ngành đánh đề

Thái | Hacker | Kỹ sư tin tặc • 39 implied HN points • 27 Dec 19
🔬 Science Cryptography
  1. When faced with challenges involving prime numbers, clever algorithms can help quickly eliminate composite numbers and pinpoint the secret numbers.
  2. The difficulty of a problem depends on the randomness of number selection within a matrix and the position of prime numbers.
  3. Designing a fair random number generation system is crucial for ensuring transparency, not only in intellectual competitions but also in traditional gambling industries.

Làm an toàn thông tin thì học gì?

Thái | Hacker | Kỹ sư tin tặc • 139 implied HN points • 02 May 12
🕹 Technology Cryptography
  1. Information security is a broad field with many areas of expertise, so it's important to choose a focus that interests you.
  2. Key roles in information security include product security, operations security, applied security, and threat analysis.
  3. To excel in information security, developing strong programming skills, mastering tools like IDA Pro, and understanding concepts in areas like cryptography and network security are essential.

alice and bob

Thái | Hacker | Kỹ sư tin tặc • 19 implied HN points • 23 Mar 08
🕹 Technology Cryptography
  1. The post discusses the concept of encryption through a rap called "Alice and Bob". It highlights the importance of protecting messages and data.
  2. Various encryption techniques and algorithms like DES, Twofish, and Blowfish are mentioned in the rap, emphasizing the significance of secure communication.
  3. The rap also touches on the importance of random number generation, RSA encryption, and hashing functions like SHA-1 for maintaining data integrity and security.

The Public Goods Funding Landscape

Splitting Infinity • 0 implied HN points • 15 Oct 23
🔬 Science Cryptography
  1. Public goods are resources that are nonexcludable and nonrivalrous, and modern technology is making some private goods resemble public goods.
  2. Mechanisms for funding public goods face challenges like the free-rider problem and impossibility theorems regarding efficiency, incentive compatibility, individual rationality, and budget balance.
  3. Different mechanisms like assurance contracts, Vickrey-Clarke-Groves mechanism, quadratic funding, lotteries, and the Lindahl process aim to address the public goods funding problem, each with its own strengths and challenges.

How E2E Encryption works it magic? + Signal Protocol

The ZenMode • 0 implied HN points • 25 Feb 24
🕹 Technology Cryptography
  1. Encryption is like a secret code that keeps your information safe and private using algorithms and keys.
  2. End-to-end encryption ensures that only the sender and recipient can access and read messages, offering a high level of security and privacy.
  3. Signal Protocol, with features like the Double Ratchet Algorithm, is widely used in popular messaging apps to provide strong security for user communications.

Stuff for the Stash, Week 6-8

INT3 / Low-level Cybersecurity • 0 implied HN points • 24 Feb 23
🕹 Technology Cryptography
  1. Mercedes-Benz plans to develop its in-house vehicle operating system named MB.OS with Google and NVIDIA partnerships.
  2. NIST announced Ascon as the lightweight cryptography standard for small devices like sensors.
  3. A collection of resources on 'Prompt Engineering' raises questions on prompt security vulnerabilities and benefits.