PicoCTF_2017: Digital Camouflage

Category: Forensics Points: 50 Description:

We need to gain access to the school routers to cover our tracks. Let's try and see if we can find the password in the network data we captured earlier: data.pcap

Hint:

It looks like an Administrator might have accessed the routers earlier. He had to have logged in with his password. Where would log in data be located in a network capture?

Write-up

Looking up the data.pcap file in Wireshark lands us with packet #122

HTML Form URL Encoded: application/x-www-form-urlencoded
    Form item: "userid" = "randled"
        Key: userid
        Value: randled
    Form item: "pswrd" = "OFBGRW8wdHRIUQ=="
        Key: pswrd
        Value: OFBGRW8wdHRIUQ==

Trying OFBGRW8wdHRIUQ== as the flag results in invalid... but wait, that looks like base64!

$ echo "OFBGRW8wdHRIUQ==" | base64 -d
8PFEo0ttHQ

Therefore, the flag is 8PFEo0ttHQ.