Saturday, November 2, 2024
HomeBackdoorLinux Backdoor that Creates Fully Encrypted Reverse Shell and Attack Unsecured Linux...

Linux Backdoor that Creates Fully Encrypted Reverse Shell and Attack Unsecured Linux Systems

Published on

Malware protection

A dangerous Linux backdoor Chaos that targeting improperly Secured Linux systems by using fully encrypted and integrity checked reverse shell.

Hackers performing  SSH brute-force attacks on Linux systems that secured by weak password and executing the Chaos Backdoor.

Chaos Backdoor was part of the  ‘sebd’ rootkit that was active around 2013 and now it is discovered via Honeypot system.

- Advertisement - SIEM as a Service

Initially, attackers compromised one of the honeypot systems by brute-forcing SSH credentials using Tor network.

Also Read:  Zero Day Attack Prevention: A Fundamental Pillar of Security

How does this Linux Backdoor Works

Attacker initially disabled the logging history an checked the SSHD binary to make sure the system did not compromise by any other attackers.

Most of the SSH attacks initiated by check the patched SSHDs to log stolen SSH credentials.

Attack initially download an image file that pretended to be a jpg from  http://xxx.xxx.xxx.29/cs/default2.jpg but the original file was distributed with .tar. so .jpg extension makes more legitimate for the victim to open it.

Chaos Backdoor that archived in .tar is the original backdoor that installed on the victim’s system and the “Client” file is the client to connect to the installed backdoor.

After installing into the Linux System and getting reverse shell, attacker distributing two files that is Chaos and Client. here, Chaos works as a backdoor and client will help to connect-back from chaos.

According to gosecure, It was interesting to see that both parties have the same two keys, which are used for sending and receiving. The encrypted password turned out to be hardcoded which we managed to crack and get the password in plain text. The password seems to be reused across different infections. 

This backdoor simply changed the name from e ‘sebd’ rootkit. and in this case, the original backdoor was stolen and used here by changing the name and make it believe it is a newly created backdoor.

The Chaos backdoor is pretty interesting as it uses a stealthy raw socket to spawn a reverse-shell with full network encryption and integrity checks. However, the backdoor’s encryption can easily be broken if the pre-shared key is known, as it is transmitted in clear text. concluded by gosecure.

IOC File Hashes

Balaji
Balaji
BALAJI is an Ex-Security Researcher (Threat Research Labs) at Comodo Cybersecurity. Editor-in-Chief & Co-Founder - Cyber Security News & GBHackers On Security.

Latest articles

LightSpy iOS Malware Enhanced with 28 New Destructive Plugins

The LightSpy threat actor exploited publicly available vulnerabilities and jailbreak kits to compromise iOS...

ATPC Cyber Forum to Focus on Next Generation Cybersecurity and Artificial Intelligence Issues

White House National Cyber Director, CEOs, Key Financial Services Companies, Congressional and Executive Branch...

New PySilon RAT Abusing Discord Platform to Maintain Persistence

Cybersecurity experts have identified a new Remote Access Trojan (RAT) named PySilon. This Trojan...

Konni APT Hackers Attacking Organizations with New Spear-Phishing Tactics

The notorious Konni Advanced Persistent Threat (APT) group has intensified its cyber assault on...

Free Webinar

Protect Websites & APIs from Malware Attack

Malware targeting customer-facing websites and API applications poses significant risks, including compliance violations, defacements, and even blacklisting.

Join us for an insightful webinar featuring Vivek Gopalan, VP of Products at Indusface, as he shares effective strategies for safeguarding websites and APIs against malware.

Discussion points

Scan DOM, internal links, and JavaScript libraries for hidden malware.
Detect website defacements in real time.
Protect your brand by monitoring for potential blacklisting.
Prevent malware from infiltrating your server and cloud infrastructure.

More like this

Researchers Backdoored Azure Automation Account Packages And Runtime Environments

Runtime environments offer a flexible way to customize Automation Account Runbooks with specific packages....

Hackers Using Supershell Malware To Attack Linux SSH Servers

Researchers identified an attack campaign targeting poorly secured Linux SSH servers, where the attack...

UNC2970 Hackers Attacking Job Seekers Using Weaponized PDF Reader

UNC2970, a North Korean cyber espionage group, used customized SumatraPDF trojans to deliver MISTPEN...