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Level Goal
The password for the next level is stored in the file data.txt, which contains base64 encoded data
Commands you may need to solve this level: grep, sort, uniq, strings, base64, tr, tar, gzip, bzip2, xxd
Walkthrough
If we do an ‘ls -la’ we see that there is an file data.txt in the home directory. Lets see what kind of file this is.
file data.txt
It has an ASCII text that is base64 encoded as the goal of the level says. Lets see the manpage of base64.
man base64
Looking at the manpage we can decode it using the -d option.
base64 data.txt
It prints: The password is IFukwKGsFW8MOq3IRFqrxE1hxTNEbUPR
This is the password for level 11.