[hyper_reality]

This is fascinating and a great bit of work by Stefan Marsiske. Loved the technical writeup in PoC||GTFO too. This quote from the TFA really shows just how difficult it was for the public to access decent cryptography at the time:

> In her book Operatie Vula, Conny Braam explains how one of her people met a guy, by the name of Floris, in a pub in Amsterdam, who allegedly had developed the PX-1000 [5]. From him they learned that the device had been taken off the market as its encryption was too strong. It had been replaced by a calculator but he suggested to find the older version with built-in crypto.

In all I would say it was a pretty good backdoor for the early 80s, showing how far ahead the NSA's internal understanding of cryptography was. I wonder if they would have anticipated the world we live in today where state-of-the-art cryptography is available and used by everyone on the Internet.

[mstef]

thank you! may i return the compliments? i love playing on cryptohack.org so many fun and educational challenges! kudos!