Here are episodes 18 to 20 of my comic strip “Chief Security Officer”.

op011 is a new internet game, the organizer of which is unknown. Readers who liked Cicada 3301 and Tengri 137 should take a closer look at it.

Chip implants for humans have been around for over a decade. They have triggered many a discussion but are very rarely used. Now a US company has announced to implant microchips in its employees.

At least 50 persons have claimed to have deciphered the Voynich Manuscript. A simple test I have developped helps to check whether a solution is correct.

A video clip of US rock band Linkin Park shows a wall with an encrypted inscription. Can a reader decipher it?

A few days ago I blogged about an unknown cipher disk from Pleidelsheim, Germany. Now a reader has sent me pictures of a very similar device. It stems from Norway.

A member of a genealogy forum has posted an encrypted text that was left behind by an ancestor of his. Can a reader solve this mystery?

Dutch collectors Paul Reuvers and Marc Simons own a simple, but carefully made cipher disk produced by Linge in Pleidelsheim. Can a reader help to find out more about this device?

Today I am going to introduce a simple asymmetric encryption system. It’s not suitable for practical use, but very helpful for explaining how public key cryptography works.

Again, a new research work about the Voynich manuscript has been published. The author believes that the famous book was created by an Italian jew. Does this hypothesis make sense? Is the author trustworthy?