Block Cipher Modes of Operation: A Primer

Block ciphers, as the name suggests, encrypt a cleartext by splitting it into individual blocks. Therefore, a key property of […]

Boston Key Party CTF Crypto-200

I love using sponges for crypto Who doesn’t, right? This past weekend was the Boston Key Party (BKP) CTF which […]

Create an Encrypted Leave-Behind Device

Consider this scenario:  You’ve breached the physical perimeter of the target organization.  Once inside, you need to establish some means […]

Let’s Hack! Part 2: Using Certificates From “Let’s Encrypt”

This is the second post of a two-part series, so if you haven’t read part one yet, stop reading, and go do […]

Let’s Hack! Part 1: Using Certificates From “Let’s Encrypt”

In case you haven’t heard, in early December 2015, Let’s Encrypt entered Public Beta, meaning that anyone can get a […]

Encryption Basics: HMAC

We have covered a method for key exchange, and we have covered a way to implement public key encryption and […]