Single-byte XOR cipher

The hex encoded string:


... has been XOR'd against a single character. Find the key, decrypt the message.

You can do this by hand. But don't: write code to do it for you.

How? Devise some method for "scoring" a piece of English plaintext. Character frequency is a good metric. Evaluate each output and choose the one with the best score.

Achievement Unlocked

You now have our permission to make "ETAOIN SHRDLU" jokes on Twitter.

Cryptography Services | NCC Group