Using Wireshark to Identify Malicious Network Activity

1. Use your preferred VNC client to connect to the host using the provided public IP on port 5901.
2. Run the commands sudo apt-get update and sudo apt-get install -y wireshark.
3. When asked if you want to allow non-superusers to capture packets, select Yes.

Download the following PCAP files to the Downloads directory:

• https://github.com/linuxacademy/content-cysa-wiresharkanalysis/blob/master/dns-tunneling.pcap
• https://github.com/linuxacademy/content-cysa-wiresharkanalysis/blob/master/beaconing.pcap

1. Use Gedit to create a file named firewall-rules.txt and save it on the Desktop.
2. Review the two packet captures and identify the source and destination involved in beaconing and DNS tunneling, and create a rule for each of the two activities.
3. The firewall-rules.txt file should contain two access lists which following the format outlined in the Guide. Remember Linux is case sensitive.
4. The firewall rule to block beaconing is:
   access-list BLOCK deny TCP 192.168.122.212/32 188.120.247.14/32 eq 80
5. The firewall rule to block DNS tunneling is:
   access-list BLOCK deny UDP 10.0.2.30/32 10.0.2.20/32 eq 53