from HackArmour

Setup

came with executable (exfiltration)

hexedit and binwalk showed arm instruction set and a few words but nothing of use

running it produces :

Инструмент эксфильтрации            
Работающий...

отправленная информация (1 байт)...[OK]

...(48 times TOTAL)

отправленная информация (1 байт)...[OK]
АдИос

which translates to:

exfiltration tool

working....

information sent (1 Byte)..[OK]

...(48 times Total)

information sent (1 Byte)..[OK]

adios

Lets get going

I pcap’d networking to see what packets were being sent with

tcpdump -w savetofile.pcap

opened the file in wireshark - important, my computer sends a lot of packets for other applications (spotify, arp etc), I closed those, but the output still wasn’t clean, I had to guess that the 48 “information sent” outputs corresponded to 48 DNS queries in wireshark

example:

48 6.940687 10.0.0.8 8.8.8.8 DNS 70 Standard query 0x0054 A amazon.com

I tried looking through to see what was different, turns out the “transaction id” was different in each DNS query, in the above example, its 0x0054. I took all 48 DNS queries and looked at the transaction id and wrote them in order here:

47 72 65 65 74 69 6e 67 73 21 20 54 68 65 20 74 6f 6b 65 6e 20 66 6f 72 20 74 68 69 73 20 67 61 6d 65 20 69 73 20 4b 47 46 44 49 44 51 53 51 54

convert this to hex gets you:

Greetings! The token for this game is KGFDIDQSQT Which was the flag

Tools

Wireshark