Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2021/02/us-cyber-command-valentines-day-cryptography-puzzles.html
The US Cyber Command has released a series of ten Valentine’s Day “Cryptography Challenge Puzzles.”
Slashdot thread. Reddit thread. (And here’s the archived link, in case Cyber Command takes the page down.)