OpenSSL 4.1.0(github.com)
165 points by petecooper | 55 comments
GitHub release page for OpenSSL 4.1.0, a feature release adding DTLS 1.3, GREASE support, ML-DSA/ML-KEM optimizations, and dropping legacy Windows targets.
#cryptography on Hacker News
49 stories tagged cryptography, newest first.
Solving the 1950 cipher meant to test life after death(creilly11235.github.io)
9 points by creilly11235 | 6 comments
Colin Reilly's write-up of solving T. E. Wood's 1950 survival-test cryptogram via computer search, finding the key in the Lord's Prayer from a 1912 Luther Bible.
Show HN: RawLink – Building a VPN protocol from scratch(github.com)
11 points by znano | 0 comments
GitHub repository for RawLink, an experimental VPN protocol built from scratch, with an accompanying blog post explaining its design.
How RC2's π table was made(khalidhamadeh.com)
5 points by KhalidH | 1 comments
A research note reconstructing how the 256-byte PITABLE in Ron Rivest's RC2 cipher key schedule was derived from π, using a card shuffle with π's digits as dice.
Galois Finite Fields and the Advanced Encryption Standard (AES)(cs.uaf.edu)
76 points by ankitg12 | 9 comments
University lecture notes from UAF CS 463/480 explaining Galois field GF(2^8) arithmetic and its role in the AES encryption algorithm.
The NIST Elliptic Curves Seeds Bounty Has Been Claimed(words.filippo.io)
29 points by aburan28 | 3 comments
Blog post by Filippo Valsorda announcing that the bounty for finding the origin of the NIST elliptic curve seeds has been claimed.
Claude reveals ECDSA curve origins(anthropic.com)
989 points by ahlCVA | 363 comments
Anthropic Frontier Red Team post saying Claude explained the long-mysterious origins of the seeds behind the ECDSA standard curves, attributing them to timestamps.
CKKS – Addition and Multiplication(jeremykun.com)
9 points by ibobev | 0 comments
A tutorial article from Jeremy Kun's Math ∩ Programming series explaining and implementing ciphertext addition and multiplication in the CKKS homomorphic encryption scheme.
![Screenshot of cr.yp.to: The cryptoint library (2025) [pdf]](https://hn.urlbox.com/shots/renders/2026/10/17/d7252175-f03a-4bd6-9d9e-1f6d618c09c4.jpg)
The cryptoint library (2025) [pdf](cr.yp.to)
21 points by akkartik | 0 comments
Daniel J. Bernstein's paper describing cryptoint, a C/C++ library of constant-time integer functions designed to resist compiler optimizations that introduce timing leaks.
Why I Wrote PGP (1991, revised 1999)(philzimmermann.com)
174 points by GaryBluto | 65 comments
Phil Zimmermann's essay from the original 1991 PGP User's Guide, updated in 1999, explaining why he created PGP to protect the privacy of personal communications.
Nexus-Q: un motor open source de Rust para PQC(nexus-q.link)
3 points by ManuelAxiom | 0 comments
Project site for Nexus-Q, an open-source Rust engine for post-quantum cryptography (PQC).
AI models can provably hide arbitrary capabilities(arxiv.org)
252 points by sbulaev | 118 comments
An arXiv paper showing AI models can embed encrypted neural network backdoors that provably hide arbitrary capabilities from elicitation-based safety evaluations.
The Gold-Bug: Edgar Allan Poe's story that taught me about cryptography (2024)(robotsinplainenglish.com)
61 points by ripe | 16 comments
A blog post on Robots in Plain English recounting how Edgar Allan Poe's story The Gold-Bug introduced the author to cryptography.
(Post-Quantum) Cryptographic Right Answers(words.filippo.io)
74 points by gavide | 13 comments
Blog post by Filippo Valsorda giving updated 'Cryptographic Right Answers' recommendations for developers, covering post-quantum cryptography choices.
How to hack time, with C2PA(da.vidbuchanan.co.uk)
50 points by Retr0id | 6 comments
Blog post by David Buchanan (retr0id) on manipulating or forging timestamps in C2PA content provenance metadata.
SequenceHash: Multihashing for the rest of us(blog.trailofbits.com)
9 points by tob_scott_a | 0 comments
Trail of Bits blog post introducing SequenceHash and SequenceMAC, open-source hash constructions for secure multihashing with unambiguous input encoding, part of C2SP.
Show HN: A working 3D model of an Enigma machine(enigma.design)
87 points by primitivesuave | 32 comments
An interactive 3D model of the WWII Enigma cipher machine that lets visitors explore how its internal mechanics encrypt messages.
Golang: Crypto/fips140: do not bloat crypto code unnecessarily(github.com)
10 points by zx2c4 | 1 comments
A GitHub issue proposing that Go's crypto/fips140 code, especially its RNG, stop adding memory and binary-size overhead for users who don't enable FIPS mode.
GPT-6 Astra Solves a WWI German Radio Cipher(prinzai.com)
367 points by nsoonhui | 168 comments
Substack post by Prinz describing how an AI model called GPT-6 Astra solved a WWI German radio cipher from a list of 50 unsolved ciphers.
I've factored the RSA keys of a Certificate Authority from the 90s(mcpherrin.ca)
461 points by ahlCVA | 106 comments
Blog post by Matthew McPherrin describing factoring the RSA keys of a 1990s-era certificate authority and what it says about RSA security.
Going Dark, and the era of law enforcement hacking(blog.cryptographyengineering.com)
438 points by vslira | 232 comments
Matthew Green blog post reflecting on Usenix Security and how AI may affect encryption, the 'going dark' debate, and law enforcement hacking.
Google is making private AI practical with homomorphic encryption(blog.google)
473 points by u1hcw9nx | 276 comments
Google Security blog post by Jeremy Kun on how Google is using homomorphic encryption to make privacy-preserving AI practical.
How Shamir's Secret Sharing Works(ente.com)
351 points by subract | 65 comments
Ente blog post explaining how Shamir's Secret Sharing splits a secret into pieces so that a threshold of them can reconstruct it.
Replace IBM Quantum back end with /dev/urandom(github.com)
337 points by pigeons | 44 comments
A GitHub markdown document in a forked repo showing that a Q-Day Prize quantum ECDLP attack submission works equally well when the IBM Quantum backend is replaced with /dev/urandom.
A cryptography engineer's perspective on quantum computing timelines(words.filippo.io)
516 points by thadt | 209 comments
Filippo Valsorda's blog post giving a cryptography engineer's view on quantum computing timelines and the urgency of deploying quantum-resistant cryptography.
What not to write on your security clearance form (1988)(milk.com)
453 points by wizardforhire | 197 comments
Les Earnest's 1988 RISKS post recounting how a childhood cipher code earned him an FBI record and complicated his later security clearance.
Reticulum, a secure and anonymous mesh networking stack(github.com)
334 points by brogu | 87 comments
GitHub repository for Reticulum, a cryptography-based networking stack for building resilient mesh networks over LoRa, packet radio, WiFi and other media.
A Vulnerability in Libsodium(00f.net)
323 points by raggi | 47 comments
Blog post by Frank Denis, libsodium's author, describing a vulnerability found in the libsodium cryptographic library.
Gpg.fail(gpg.fail)
426 points by todsacerdoti | 282 comments
Placeholder page for gpg.fail, apparently a disclosure site about GnuPG vulnerabilities, showing only the message "brb, were on it!!!!".
Claude Code can debug low-level cryptography(words.filippo.io)
446 points by Bogdanp | 199 comments
Filippo Valsorda's blog post on using Claude Code to debug his new Go implementation of the ML-DSA post-quantum signature algorithm.
“This telegram must be closely paraphrased before being communicated to anyone”(history.stackexchange.com)
720 points by azeemba | 126 comments
A History Stack Exchange question asking why WWII telegrams carried the notice that they must be closely paraphrased before being communicated to anyone.
Fully homomorphic encryption and the dawn of a private internet(bozmen.io)
395 points by barisozmen | 183 comments
Personal blog essay by Barış Özmen explaining fully homomorphic encryption and how it could enable a truly private internet.
Why SSL was renamed to TLS in late 90s (2014)(tim.dierks.org)
520 points by Bogdanp | 223 comments
Tim Dierks' 2014 blog post explaining how Netscape-Microsoft browser war politics led SSL to be standardized and renamed as TLS.
The radix 2^51 trick (2017)(chosenplaintext.ca)
398 points by blobcode | 78 comments
Blog post explaining the radix 2^51 representation trick for faster multi-precision addition and subtraction on modern CPUs by deferring carry propagation.
15,000 lines of verified cryptography now in Python(jonathan.protzenko.fr)
447 points by todsacerdoti | 142 comments
Blog post by Jonathan Protzenko describing how CPython now uses the formally verified HACL* library for all its default hash and HMAC algorithms.
Bletchley code breaker Betty Webb dies aged 101(bbc.com)
482 points by danso | 90 comments
BBC News obituary reporting that Bletchley Park code breaker Betty Webb has died at the age of 101.
XOR(chiark.greenend.org.uk)
541 points by mariuz | 91 comments
Simon Tatham's long-form essay explaining the XOR operation in boolean logic and on integers, its properties, and applications such as cryptography, graphics, and swaps.
Homomorphic encryption in iOS 18(boehs.org)
359 points by surprisetalk | 193 comments
Blog post by Evan Boehs explaining homomorphic encryption in iOS 18 for non-math readers, prompted by controversy over Apple Photos phoning home.
Cracking a 512-bit DKIM key for less than $8 in the cloud(dmarcchecker.app)
769 points by awulf | 370 comments
An article describing how the authors factored a 512-bit RSA DKIM public key using cloud computing for under $8 and tested forged email signatures against major providers.
Code that helped end Apartheid(wired.com)
331 points by impish9208 | 179 comments
Wired article by Steven Levy on how Cloudflare CTO John Graham-Cumming decrypted a 30-year-old file of code used in the covert communications that helped end apartheid.
EUCLEAK Side-Channel Attack on the YubiKey 5 Series(ninjalab.io)
678 points by GTP | 258 comments
NinjaLab's page on EUCLEAK, a side-channel attack recovering ECDSA keys from YubiKey 5 Series devices using Infineon security microcontrollers.
Is Telegram really an encrypted messaging app?(blog.cryptographyengineering.com)
523 points by md224 | 473 comments
Blog post by cryptographer Matthew Green examining whether Telegram actually qualifies as an encrypted messaging app, given its default lack of end-to-end encryption.
Should I use JWTs for authentication tokens?(blog.ploetzli.ch)
536 points by pantalaimon | 367 comments
Blog essay by Henryk Plötz arguing that JSON Web Tokens should not be used as authentication/session tokens, explaining the reasons.
Cryptographers solve decades-old privacy problem(nautil.us)
324 points by Brajeshwar | 124 comments
Nautilus article by Madison Goldberg on cryptographers' advance toward fully private database lookups and internet searches (private information retrieval).
NIST Elliptic Curves Seeds Bounty(words.filippo.io)
397 points by mfrw | 83 comments
Filippo Valsorda's blog post announcing an $8,192 bounty for recovering the original seeds used to generate the NIST elliptic curves.
Debunking NIST's calculation of the Kyber-512 security level(blog.cr.yp.to)
415 points by bumbledraven | 175 comments
Daniel J. Bernstein's blog post arguing that NIST miscalculated Kyber-512's security level by multiplying costs that should have been added.
NSA Backdoor Key from Lotus-Notes (1997)(cypherspace.org)
330 points by hosteur | 141 comments
Adam Back's page describing how he reverse-engineered Lotus Notes to extract the NSA key-escrow public key, named "MiniTruth"/"Big Brother", used in export versions.
Messages that can only be understood under the influence of psychedelics(qri.org)
561 points by robinhouston | 252 comments
Qualia Research Institute blog post announcing a contest to create 'psychedelic cryptography': messages decodable only in non-ordinary states of consciousness.
See this page fetch itself, byte by byte, over TLS(subtls.pages.dev)
1261 points by gmac | 153 comments
Interactive demo page that performs a live, annotated HTTPS request for its own source using subtls, a pure-JavaScript TLS 1.3 implementation.