C2 Active Monitoring

Collecting orders from Command and Control servers by impersonating an infected machine


@xanhacks

https://slides.com/xanhacks/c2-active-monitor/

whoami

# whoami
C2 Active Monitoring - @xanhacks
  • Student at ENSIBS
  • Malware Analyst at the French Post Office
  • Play CTF in my free time (Web & Reverse)

@xanhacks

Demo time!

# whoami
C2 Active Monitoring - @xanhacks

Samples & C&C servers

# introduction
C2 Active Monitoring - @xanhacks

Samples (malicious files)

Types:

  • Wiper
  • Ransomware
  • Dropper
  • RAT (Remote Administration Tool)
  • Stealer...

Format:

  • Scripts, EXE, LNK, DLL, Archive...

C&C or C2 (Command & Controls)

Goal: Communicate with samples/victims.

Protocols:

  • HTTP/HTTPs, TCP, DNS...

Features:

  • Fingerprints, Geofencing, List of C&C, Proxies, P2P, Dynamic DNS...

Infection chain

C2 Active Monitoring - @xanhacks

https://blog.sekoia.io/nobeliums-envyscout-infection-chain-goes-in-the-registry-targeting-embassies/

https://www.trellix.com/blogs/research/qakbot-evolves-to-onenote-malware-distribution/

# introduction

Infection entrypoint

https://blog.sekoia.io/clickfix-tactic-revenge-of-detection/

https://www.mcafee.com/blogs/other-blogs/mcafee-labs/rising-trend-of-onenote-documents-for-malware-delivery/

https://www.logpoint.com/en/blog/security-analysis/html-smuggling-detection-essentials/

# introduction

C&C Infrastructure

# introduction

https://www.cisa.gov/news-events/cybersecurity-advisories/aa23-242a

Direct connection

Anonymization layers

Why monitoring C2 servers?

# example: njrat
C2 Active Monitoring - @xanhacks
Technical goal Adjectives
Collecting fresh IoC (live communication) Temporality
IoC without false positives Quality
IoC after the compromission Quantity

IoC (Indicator Of Compromise): artifact observed on a network (IP address, DNS...) or in an operating system (Hash, Registry key, files...) that, with high confidence, indicates a computer intrusion.

 Improve detection & CTI.

Case Study: NjRAT - Green Edition

# example: njrat
C2 Active Monitoring - @xanhacks

NjRAT Sample

  • Remote Access Trojan
  • Made in .NET
  • TCP protocol

NjRAT Panel (Green Edition - Attacker POV)

Why NjRAT? Still famous in 2024...

# example: njrat
C2 Active Monitoring - @xanhacks

Top 10 on Malware Trends (any.run)

Leaked C&C Panel

How it works

# how it works

MWDB

Malware Database

Karton

Configuration extraction

Downloader

Download samples

C2 Active Monitoring - @xanhacks

Download samples

# how it works

MalwareBazaar & Tria.ge API

VT Enterprise - Live Hunt API

Download samples

# how it works

Well-known malware databases

  • VirusTotal (enterprise account)
  • Tria.ge (free - account needed)
  • MalwareBazaar (free - no account needed)

MWDB Sample List

# how it works
C2 Active Monitoring - @xanhacks

MWDB Sample Overview

# how it works
C2 Active Monitoring - @xanhacks

Karton - Run tasks on samples

# how it works
C2 Active Monitoring - @xanhacks

New sample

Tasks

  • Configuration Extractor
  • Unpacker
  • Archive Extractor

Upload config

to MWDB

How it works

# how it works

C2 Monitoring API

API & database for C2 & Orders

C2 Connectors

Python scripts to

communicate with C2

C2 Active Monitoring - @xanhacks

C2 Servers

One class for each

malware family

NjratClient

XWormClient

Web Interface

How it works - Part 2 - C2 Monitor Overview

# how it works
C2 Active Monitoring - @xanhacks

How it works - Part 2 - C2 Monitor Orders

# how it works
C2 Active Monitoring - @xanhacks

Case Study: NjRAT - Green Edition

# example: njrat
C2 Active Monitoring - @xanhacks

NjRAT is a Remote Access Trojan made in .NET that communicates through unencrypted TCP socket

(default port: 5552)

Funny Orders - Fun Popup

# results
C2 Active Monitoring - @xanhacks

Funny Orders - Chat Plugin

# results
C2 Active Monitoring - @xanhacks

Funny Orders - Open Site - Russian Video

# results
C2 Active Monitoring - @xanhacks

Funny Orders - Open Site - Russian Video again...

# results
C2 Active Monitoring - @xanhacks

Campaign - "I am Furry"

# results
C2 Active Monitoring - @xanhacks
# results
C2 Active Monitoring - @xanhacks

Timeline

Campaign - "I am Furry"

"ill fucking kill your computer"
"im getting your bank information"
"you will be fucking poor"

# results
C2 Active Monitoring - @xanhacks

https://www.youtube.com/watch?v=Xs3ukQql0H0

Wiper #1:

AiVDsDOsA

Campaign - "I am Furry"

# results
C2 Active Monitoring - @xanhacks

https://www.youtube.com/watch?v=jK1nRADpVnw

Wiper #2:

Neptunium

Campaign - "I am Furry"

# results
C2 Active Monitoring - @xanhacks

Furry lover <3

Campaign - "I am Furry"

Campaign - @gribojuy / ГРИБОЖУЙ / Champignon

# results
C2 Active Monitoring - @xanhacks

> "gribojuyy" enter the chat

gribojuyy: Bro, hello, do you have paypal?

me: What are you doing in my computer ?

gribojuyy: do you have a discord?

me: Where are you from ?

gribojuyy: America

gribojuyy: bro do you have telegram

gribojuyy: bro do you have telegram

gribojuyy: bro do you have telegram

gribojuyy: ...

gribojuyy: message me in telegram @gribojuy

Chat exchange on 10/05/2024

At the same time:

  • Record Micro/Cam
  • Open PH (also send index.html)
  • Play piano
  • Process List
  • Text to Speech (if i do not answer to chat)

Campaign - @gribojuy - Telegram & YouTube

# results
C2 Active Monitoring - @xanhacks

Campaign - @gribojuy - Telegram Preview

# results
C2 Active Monitoring - @xanhacks

Campaign - @gribojuy - Pastebin Account

# results

Campaign - @gribojuy - Github Account

# results

The nice guy

# results
C2 Active Monitoring - @xanhacks

Timeline

"You installed a virus that I did not distribute"

"Please install antivirus"

MessageBox: Documentation to remove NjRAT

Coincidence??

# results
C2 Active Monitoring - @xanhacks

14min interval

Anydesk IT Support from Russia

# results
C2 Active Monitoring - @xanhacks

14/04/2024

ME ATTACKER
Who are you?
i m russian student
How much money do you make in a month ?
5000$
What do you want ?
bro i can delete this virus but you must download anydesk program and give me anydesk code

Mindset entrepreneurs

# results
ME ATTACKER
How much money do you make in a month ?
and you?
What are you doing in my computer ?
you launched my warrior
What do you want ?
What is your job?
Answer the question and I'll leave
What is your job? What is your job?

Mindset entrepreneurs #2

# results
ME ATTACKER
What are you doing in my computer ?
send me 100$ and i will get out from your computer
Where are you from ?
you dont need to know this send me money or i will shut down your computer and you will never get access to
Can you hack my girlfriend facebook account ?
ok how much you will give me

The bilingual

# results
ME ATTACKER
What do you want ?
ты приёмный
(You are adopted)
Can you please get out of my computer ?
црфе
Can you please get out of my computer ?
sex

PvP players?

# results

PvP players? #2

# results

PvP players? #3

# results
# results
C2 Active Monitoring - @xanhacks

PvP players? #4

Rick rolled

# results

The Musician

# results

Case Study: Houdini & Co

# example: njrat

Houdini is a RAT made in VBS/JScript that communicates through HTTP

Object Oriented Programmboting

# example: njrat

Vw0rm

WshRAT

WshRAT v2

LimeWorm

Houdini

VBSBot

Detecting the correct malware family at runtime

# example: njrat

DL

UP

EXEC

PROXY

UNINSTALL

RED

YELLOW

GREEN

Plus c'est gros plus ça passe!

# results

Virtuous circle

# how it works

MWDB

Malware Database

DarkComet

C2 Active Monitoring - @xanhacks

AsyncRAT

Karton

Configuration extraction

Challenges

InfeXion - Reverse a multi-steps Infection chain
https://github.com/HeroCTF/HeroCTF_v5/tree/main/Reverse/InfeXion_1

 

AutoInfector - Reverse a Malware & Interact with the C2

https://github.com/HeroCTF/HeroCTF_v6/tree/main/Reverse/AutoInfector_1

 

MalNET - Reverse a .NET malware

https://app.flag4jobs.com/challenges/malnet

 

MineCrack & SimpleCase - Forensic cases with malwares
https://app.flag4jobs.com/challenges/minecrack
https://app.flag4jobs.com/challenges/simplecase

End!

Any questions ?

 

@xanhacks

https://slides.com/xanhacks/c2-active-monitor/

C2 Active Monitor

By xanhacks

C2 Active Monitor

  • 433