Stolen Mount

Challenge 26: An intruder has infiltrated our network and targeted the NFS server where the backup files are stored. A classified secret was accessed and stolen. The only trace left behind is a packet capture (PCAP) file recorded during the incident. Your mission, should you accept it, is to discover the contents of the stolen data.

Solution

Start the machine and open the the pcapng file in Wireshark for analysis.
A password hash is mentioned, we crack the password using crackstation easily.
We are already provided with NFS communication. After Analyzing a bit, it is observed that hidden_stash.zip file is transferred being transferred.
Since its a zip file, we know it starts with PK (Magic bytes)
Copy the content of packet which starts with in raw format.

We need to convert the raw hex data to binary and then extract the zip.

import binascii

# Read the hex dump from a file (or use a string directly)
hex_data = """<Add the Raw data here>"""

bin_data = binascii.unhexlify(hex_data.replace("\n", ""))

with open("extracted.zip", "wb") as f:
    f.write(bin_data)

print("ZIP file created. use unzip with password to extract its content")

Extract the content and view the image, it is a QR code. Resolve the QR code using mobile phone. That is the answer.