Challenge Description

Danish (original)

Vi har modtaget efterretning om, at en spion i Asgard har været i kontakt med jætternes spion-hotline. Vi har opsnappet et telefonopkald, hvor spionen indtastede deres spionnummer.

Vi har brug for din hjælp til at identificere det indtastede spionnummer, så vi kan komme tættere på at afsløre deres identitet.

Lav flaget ud fra FDCA{spionnummer}

Flag eksempel: FDCA{123456789}

English (from chatgpt)

We have received intelligence that a spy in Asgard has been in contact with the giants’ spy hotline. We have intercepted a phone call where the spy entered their spy number.

We need your help to identify the entered spy number so that we can get closer to revealing their identity.

Create the flag based on FDCA{spy_number}

Flag example: FDCA{123456789}

File

We are also given the following file:

Solution

Pressing numbers on the phone produces DTMF tones, so we can just use this DTMF Decoder to get the code: FDCA{012500118}