CrypTool is the world’s leading crypto e-learning software. Currently, the 20th anniversary of this outstanding tool is celebrated in Munich. Among the guests are some renowned codebreakers.

Outsider artist James Hampton’s writing in an unknown script is one of the world’s most puzzling crypto mysteries. Today, I’m going to introduce an unencrypted text that can be read on Hampton’s only artwork. As far as I know, this note has never been published before.

A few weeks ago, I introduced a 1000-letter ciphertext created with a bigram substitution. Jarl Van Eycke and Louie Helm have now solved this challenge and set a new world record.

At the NSA Symposium on Cryptologic History, I gave a presentation about brute-force attacks. After a subsequent discussion with Whitfield Diffie, I realized that we need a new DES challenge. Here it is.

Last week, the biannual NSA Symposium on Cryptologic History took place in Laurel, Maryland. Here are a few pictures from this outstanding event.

The George C. Marshall Library in Lexington, VA, has a collection of documents left behind by codebreaking genius William Friedman. Today, I’m going to introduce a crypto puzzle I found there.

Outsider artist James Hampton left behind an encrypted notebook and a sculpture bearing a few encrypted labels. When I was in Washington, D.C., recently, I took a video of both.

Blog reader Christof Rieber has sent me a potential solution of a major crypto mystery: the encrypted passages of Lady Gewndolen’s diary. Is Christof’s deciphering attempt correct?

In 1914, a man sent an encrypted postcard from Kiel to Hannoversch Münden. Contrary to all other encrypted postcards I know, this one was written with a typewriter.

At the hacker conference 44CON 2019, wich took place in September in London, I gave a talk about Cold War cryptography. Here’s a professionally produced video of it.