Masterminds | Tryhackme Writeup

Room Link: https://tryhackme.com/room/mastermindsxlq

Objectives:

• Log analysis using Brim

• Identifying suspicious domains and IP addresses

• Threat intelligence analysis

• Identifying malware types based on downloaded executables

Task 1: Detect the compromise using Brim.

Three machines in the Finance department at Pfeffer PLC were compromised. We suspect the initial source of the compromise happened through a phishing attempt and by an infected USB drive. The Incident Response team managed to pull the network traffic logs from the endpoints. Use Brim to investigate the network traffic for any indicators of an attack and determine who stands behind the attacks.

NOTE: DO NOT directly interact with any domains and IP addresses in this challenge.

Task 2: [Infection 1]

Start by loading the Infection1 packet capture in Brim to investigate the compromise event for the first machine. All the PCAPs can be found here: /home/ubuntu/Desktop/PCAPs

Note: For questions that require multiple answers, please separate the answers with a comma.

Answer the questions below

1. Provide the victim's IP address.

Ans: 192.168.75.249

The identified IP address was observed communicating with multiple suspicious domains.

2. The victim attempted to make HTTP connections to two suspicious domains with the status '404 Not Found'. Provide the hosts/domains requested.

Ans: cambiasuhistoria.growlab.es,www.letscompareonline.com

Please refer to the screenshot above for all answers.

3. The victim made a successful HTTP connection to one of the domains and received the response_body_len of 1,309 (uncompressed content size of the data transferred from the server). Provide the domain and the destination IP address.

Ans: ww25.gocphongthe.com,199.59.242.153

4. How many unique DNS requests were made to cab[.]myfkn[.]com domain (including the capitalized domain)?

Ans: 7

5. Provide the URI of the domain bhaktivrind[.]com that the victim reached out over HTTP.

Ans: /cgi-bin/JBbb8/

6. Provide the IP address of the malicious server and the executable that the victim downloaded from the server.

Ans: 185.239.243.112,catzx.exe

7. Based on the information gathered from the second question, provide the name of the malware using VirusTotal.
   Ans: Emotet

Emotet is a highly sophisticated, polymorphic botnet that uses command-and-control (C2) servers to communicate with infected machines and download secondary payloads, such as TrickBot or Cobalt Strike.

Emotet typically communicates with C2 servers to exfiltrate stolen data and receive commands.

Task 3: [Infection 2]

Please, navigate to the Infection2 packet capture in Brim to investigate the compromise event for the second machine.

Note: For questions that require multiple answers, please separate the answers with a comma.

Answer the questions below

1. Provide the IP address of the victim machine.

Ans: 192.168.75.146

how u derermin,e more traffic to outbound traffic, suspicous http requests, alerts

2. Provide the IP address the victim made the POST connections to.

Ans: 5.181.156.252

3. How many POST connections were made to the IP address in the previous question?

Ans: 3

4. Provide the domain where the binary was downloaded from.

Ans: hypercustom.top

5. Provide the name of the binary including the full URI.

Ans: /jollion/apines.exe

6. Provide the IP address of the domain that hosts the binary.

Ans: 45.95.203.28

7. There were 2 Suricata "A Network Trojan was detected" alerts. What were the source and destination IP addresses?

Ans: 192.168.75.146,45.95.203.28

8. Taking a look at .top domain in HTTP requests, provide the name of the stealer (Trojan that gathers information from a system) involved in this packet capture using URLhaus Database.

Ans: Redline Stealer

Task 4: [Infection 3]

Please, load the Infection3 packet capture in Brim to investigate the compromise event for the third machine.

Note: For questions that require multiple answers, please separate the answers with a comma.

Answer the questions below

1. Provide the IP address of the victim machine.

Ans: 192.168.75.232

The domains it is communicating with appear suspicious, indicating that the system is the victim.

2. Provide three C2 domains from which the binaries were downloaded (starting from the earliest to the latest in the timestamp)

Ans: efhoahegue.ru,afhoahegue.ru,xfhoahegue.ru

3. Provide the IP addresses for all three domains in the previous question.

Ans: 162.217.98.146,199.21.76.77,63.251.106.25

4. How many unique DNS queries were made to the domain associated from the first IP address from the previous answer?

Ans: 2

5. How many binaries were downloaded from the above domain in total?

Ans: 5

6. Provided the user-agent listed to download the binaries.

Ans: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:25.0) Gecko/20100101 Firefox/25.0

7. Provide the amount of DNS connections made in total for this packet capture.

Ans: 986

8. With some OSINT skills, provide the name of the worm using the first domain you have managed to collect from Question 2. (Please use quotation marks for Google searches, don't use .ru in your search, and DO NOT interact with the domain directly).

Ans: Phorphiex

Thank you for Reading. I hope you enjoyed this walkthrough!

Keep Hunting!