unpack-me

Solved by: grb

This is what the challenge looks like, there's a binary file attached to it.

Because of the name of the challenge, my first reflex is to use Detect-It-Easy, see if anything comes up, and something did came up.

As you can see from the DIE result, it said that the binary is packed with UPX. You can easily unpack it with UPX again.

Next, now we can get back to our usual routine. Lets open up the unpacked binary under IDA.

As you might remember, this is very similar to the crack-me challenge. The main function check if the first input is "compit" and if the second input is "packerunpack". If both condition are met, the program will print the flag. Equipped with this piece of information, we can just enter the those two inputs, and when we do, we get...

PO- PO- PO- PWNED!!!