1.4 KiB
1.4 KiB
Homework 3: Find the firmware
We start by copying the firmware capture file from ada to our machine
Reverse Engineering
First lets open this capture up in wireshark and do a high level overview
Wireshark overview
Knowing we are ultimetly looking to re-construct a firmware download, we can discern some important info from wireshark
- There are 241,531 packets in this capture, but only some are the traffic directly related to this download
- Client of the download is 192.168.86.167 and server origin is 192.168.86.228:5000
- The download is split over multiple HTTP requests by the shown convention, which themselves are split over multiple TCP requests
A starting point of a BPF might look like tcp and src host 192.168.86.228 and src port 5000 and dst host 192.168.86.167
As a wireshark filter, this would be tcp && ip.src == 192.168.86.228 && tcp.srcport == 5000 && ip.dst == 192.168.86.167
Before moving on to scapy, we can filter down our firmware.pcap to a new capture called filtered.pcap with the following command
tcpdump -r firmware.pcap -w filtered.pcap 'tcp and src host 192.168.86.228 and src port 5000 and dst host 192.168.86.167'
Questions
- What architecture is the firmware intended to run on?
- What OS is the firmware running?
- What users are present on the system?