Really interesting research into the structure of prime numbers. Not immediately related to the cryptanalysis of prime-number-based public-key algorithms, but every little bit matters. [...]

Matthew Green wrote a really good blog post on what Telegram’s encryption is and is not. EDITED TO ADD (8/28): Another good explainer from Kaspersky. [...]

Really interesting article on the ancient-manuscript scholars who are applying their techniques to the Voynich Manuscript. No one has been able to understand the writing yet, but there are some new understandings: Davis presented her findings at the medieval-studies conference and published them in 2020 in the journal Manuscript …

A group of cryptographers have analyzed the eiDAS 2.0 regulation (electronic identification and trust services) that defines the new EU Digital Identity Wallet. [...]

Interesting paper about a German cryptanalysis machine that helped break the US M-209 mechanical ciphering machine. The paper contains a good description of how the M-209 works. [...]

Interesting summary of various ways to derive the public key from digitally signed files. Normally, with a signature scheme, you have the public key and want to know whether a given signature is valid. But what if we instead have a message and a signature, assume the signature is …

This is really neat demo of the security problems arising from reusing nonces with a symmetric cipher in GCM mode. [...]

The Polish Embassy has posted a series of short interview segments with Marian Rejewski, the first person to crack the Enigma. Details from his biography. [...]

A new paper presents a polynomial-time quantum algorithm for solving certain hard lattice problems. This could be a big deal for post-quantum cryptographic algorithms, since many of them base their security on hard lattice problems. A few things to note. One, this paper has not yet been peer reviewed …

Last week I posted a short memorial of Ross Anderson. The Communications of the ACM asked me to expand it. Here’s the longer version. [...]

Last week, I posted a short memorial of Ross Anderson. The Communications of the ACM asked me to expand it. Here’s the longer version. EDITED TO ADD (4/11): Two weeks before he passed away, Ross gave an 80-minute interview where he told his life story. [...]

Ross Anderson unexpectedly passed away Thursday night in, I believe, his home in Cambridge. I can’t remember when I first met Ross. Of course it was before 2008, when we created the Security and Human Behavior workshop. It was well before 2001, when we created the Workshop on …

Apple announced PQ3, its post-quantum encryption standard based on the Kyber secure key-encapsulation protocol, one of the post-quantum algorithms selected by NIST in 2022. There’s a lot of detail in the Apple blog post, and more in Douglas Stabila’s security analysis. I am of two minds about …

The winner of the Best Paper Award at Crypto this year was a significant improvement to lattice-based cryptanalysis. This is important, because a bunch of NIST’s post-quantum options base their security on lattice problems. I worry about standardizing on post-quantum algorithms too quickly. We are still learning a …

David Kahn has died. His groundbreaking book, The Codebreakers was the first serious book I read about codebreaking, and one of the primary reasons I entered this field. He will be missed. [...]

We don’t have a useful quantum computer yet, but we do have quantum algorithms. Shor’s algorithm has the potential to factor large numbers faster than otherwise possible, which—if the run times are actually feasible—could break both the RSA and Diffie-Hellman public-key algorithms. Now, computer scientist …