HACKvent 2015: Day 4

Challenge

Clue: Crypto - a classic / simple one

HOlAfOVWOqVd1o6q7u5Vj8Mv-----

Solution

At first I was convinced this was a Vigenere cipher but this is not the case.
After a clue from M from the hacking-lab IRC channel I was able to figure out the cipher used is the Scytale cipher.
This is somewhat obvious as the - characters from the nugget are all grouped at the end of the ciphertext.

The length is also obvious by simply looking at the end of the ciphertext, l = 5.

We use an online scytale solver (link) to get the flag.

Flag:

HV15-OWoV-lO6j-Aqq8-fV7M-Oduv