Why encrypted backup is so important
You might have seen the news today that Apple is announcing a raft of improvements to Macs and iOS devices aimed at improving security and privacy. These include FIDO support, improvements to iMessage...
View ArticleRemarks on “Chat Control”
On March 23 I was invited to participate in a panel discussion at the European Internet Services Providers Association (EuroISPA). The focus of this discussion was on recent legislative proposals,...
View ArticleBook Review: Red Team Blues
As a rule, book reviews are not a thing I usually do. So when I received an out-of-the-blue email from Cory Doctorow last week asking if I would review his latest book, Red Team Blues, it took a...
View ArticlePRFs, PRPs and other fantastic things
A few weeks ago I ran into a conversation on Twitter about the weaknesses of applied cryptography textbooks, and how they tend to spend way too much time lecturing people about Feistel networks and...
View ArticleOn Ashton Kutcher and Secure Multi-Party Computation
Back in March I was fortunate to spend several days visiting Brussels, where I had a chance to attend a panel on “chat control“: the new content scanning regime being considered by the EU Commission....
View ArticleSome rough impressions of Worldcoin
Recently a reader wrote in and asked if I would look at Sam Altman’s Worldcoin, presumably to give thoughts on it from a privacy perspective. This was honestly the last thing I wanted to do, since...
View ArticleTo Schnorr and beyond (Part 1)
Warning: extremely wonky cryptography post. Also, possibly stupid and bound for nowhere. One of the hardest problems in applied cryptography (and perhaps all of computer science!) is explaining why...
View ArticleTo Schnorr and beyond (part 2)
This post continues a long, wonky discussion of Schnorr signature schemes and the Dilithium post-quantum signature. You may want to start with Part 1. In the previous post I discussed the intuition...
View ArticleAttack of the week: Airdrop tracing
It’s been a while since I wrote an “attack of the week” post, and the fault for this is entirely mine. I’ve been much too busy writing boring posts about Schnorr signatures! But this week’s news...
View ArticleA quick post on Chen’s algorithm
Update (April 19): Yilei Chen announced the discovery of a bug in the algorithm, which he does not know how to fix. This was independently discovered by Hongxun Wu and Thomas Vidick. At present, the...
View ArticleIs Telegram really an encrypted messaging app?
This blog is reserved for more serious things, and ordinarily I wouldn’t spend time on questions like the above. But much as I’d like to spend my time writing about exciting topics, sometimes the...
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