Bandit9

Website URL: http://overthewire.org/wargames/bandit/bandit9.html

Log in to the game server using credentials of bandit8 (see this for walkthrough for that level).

 

 

OverTheWire webpage for bandit9 says:

The password for the next level is stored in the file data.txt and is the only line of text that occurs only once

Well, now things are warming up! Our tools ls, cat, and grep won’t be of much use here, at least, not directly. So let’s analyze a bit.

We need to do something that will show us the count of each line in data.txt be it using a command directly or by using a custom script.

There’s a command in linux : uniq which can provide us with the unique strings in the file. We can add a parameter to it so that it shows us the count of the string as well. Modifying the command a bit by adding our old friend grep should do the trick.

But wait! Things aren’t that straightforward. A quick look into uniq command reveals that it can only identify duplicates that are adjacent to each other. That calls for a sort function. So, our final command looks like:

sort data.txt | uniq -c | grep "1 "

Note: I appended a space after the “1” in grep command. This was to make sure that it filters out occurrences such as 10, 100, 11 and so on.

As easy as a pie!