Level Goal

The password for the next level is stored in the file data.txt, where all lowercase (a-z) and uppercase (A-Z) letters have been rotated by 13 positions.

Solution

Password: IFukwKGsFW8MOq3IRFqrxE1hxTNEbUPR

Let’s take a look at data.txt.

Sure looks like ROT13.

There’s so many ways we could decode ROT13. There’s plenty of online decoders, and even a rot13 command (but it’s not installed by default). Instead, let’s use some of the base utilities. A tool that translates text is tr.

tr just translated the characters from a to z by 13 by giving a new range to map to (n-z, a-m). The same was done for the capital letters.

Joy.