If You Can Understand This Tweet, You Can Probably Get A Job At The NSA

The NSA Careers twitter account just sent out what looks like a string of gibberish. Here it is via Neetzan Zimmerman:

tpfccdlfdtte pcaccplircdt dklpcfrp?qeiq lhpqlipqeodf gpwafopwprti izxndkiqpkii krirrifcapnc dxkdciqcafmd vkfpcadf. #MissionMonday #NSA #news

- NSA (@NSACareers) May 5, 2014

However, this may be some kind of code, since the letters don't appear to be completely random.

First, all but two of the blocks are made up of exactly twelve letters. The exceptions are the third block, with a question mark in the middle bringing the total up to 13 characters, and the last block, with eight letters and a period. The question mark may be a typo or extra clue, and the last block might be shorter because it's at the end of the message.

If this were a purely accidental tweet, it's unlikely that we'd get this regularity.

Further, the letters don't appear to be distributed randomly, or in a way consistent with a keyboard mash. Some letters, like P, C, and I, appear a lot in the tweet, whereas five letters don't show up at all. Here are the letter frequencies in the tweet, as calculated with a set of online cryptanalysis tools:

A very simple type of encryption is a shift, or Caesar cipher. The alphabet is simply shifted over by some fixed distance. A Caesar cipher with a shift of 1 would send A to B, B to C, and so on, with Z wrapping back around to A. A shift of 2 would send A to C, B to D, C to E, and so on, with Y wrapping around to A and Z wrapping around to B.

We tried the Caesar cipher tool on the above site for the mystery tweet and a couple of shifts, and unfortunately came up with nothing. Here's our input to the tool, shifting by half the alphabet of 13 letters:

We got the very discouraging output below:

If you can figure this out, you may have a job waiting for you at the NSA.