Quasar RAT

Quasar is a very popular RAT in the world thanks to its code being available in the open-source. This malware can be used to remotely control the victim’s computer.

Type
Trojan
Origin
Unknown
First seen
1 January, 2015
Last seen
19 January, 2021
Global rank
13
Week rank
11
Month rank
12
IOCs
3964

What is Quasar RAT?

Quasar is a remote access trojan is used by the attackers to take remote control of infected machines. It is written using the .NET programming language and available to a wide public as an open-source project, making it a popular RAT that was featured in a number of attacks.

General description of Quasar RAT

Quasar RAT was first discovered in 2015 by security researchers, who, at the time, speculated that this RAT was written by an in-house development team after performing the analysis of a sample. Quasar is an evolution of an older malware called xRAT and some of its samples can carry out as much as 16 malicious actions.

Over the course of its lifetime, the malware has been updated several times, improving its overall functionality. The last version of the malware which was developed by the original author is v. 1.3.0.0. It was released in 2016. Since that time several third parties have adapted the RAT and issued their own version, both minor and major with the last major version being v. 2.0.0.1.

The RAT we are reviewing today consists of two main components – the server-side component and the client-side component. The server is equipped with a graphical user interface and it is used for managing connections with the client-side programs. The server-side component is also utilized to build malware samples which are eventually delivered to potential victims. Malware user has an option to select attributes and customize the executable to fit the needs of the attacker.

The functionality of the resulting malware includes remote file management on the infected machine, registry alterations, recording the actions of the victim, establishing remote desktop connections and more.

It should be noted that Quasar execution can unfold completely silently, thus, once the victim downloads and launches the client, usually delivered in a document via email, it can stay active for a long period of time, stealing data and giving the hacker control over the infected PC. The malware does generate a process that can be discovered using the Windows Task Manager or a similar application, but active user actions are required to discover Quasar trojan presence on a machine.

As far as creators of this malware are concerned, the group of people or a person behind the original version of this malware managed to remain anonymous. The little known information that we do have does not go beyond the name of the GitHub page author which states simply “quasar”.

As evident from the description on the “official” Quasar GitHub page, this malware is presented as a legitimate remote administration program, which is clearly misleading. In fact, Quasar was featured in an attack aimed at the US government early in 2017. Later the same year another wave of attacks using this malware occurred, this time targeting the private sector.

Quasar RAT malware analysis

The execution process of this malware can be viewed in a video recorded in the ANY.RUN malware hunting service, allowing to take a look at how the contamination process unfolds.

process graph of the quasar stealer execution Figure 1: Displays the lifecycle of Quasar in a visual form, as shown on the graph generated by ANY.RUN.

text report of quasar analysis Figure 2: Shows a customizable text report generated by the ANY.RUN malware hunting service.

Quasar RAT execution process

Quasar execution is pretty straightforward but can vary in minor details from sample to sample. In a given example, Quasar was dropped from a Microsoft Office file. The dropped file changed the registry value to make itself run with every operating system start, checked for external IP and also copied itself at another location. After all these steps, the malware started the main malicious activity - collecting information about the operating system and waiting for commands from the C2 server.

How to avoid infection by Quasar?

Quasar trojan writes itself into scheduled tasks and uses registry keys to achieve persistence, allowing the malware the run every time a machine is started. The persistence method is chosen based on user privileges. As such, if the user has admin rights, the malware uses schtasks to create a scheduled task which launches after a user logs on with the highest run level. If admin rights are lacking, then the scheduled task can only go as far as to add a registry value which is configured in the client builder and added to the current path as the startup program.

Distribution of Quasar RAT

Just as most of the other RATs, Quasar is distributed in email spam campaigns that carry the malware’s loader. The loader is embedded in a malicious file attachment which usually carries a name designed to trick the user into thinking that he or she is receiving some sort of a document. Sometimes these files will have a double extension such as docx.exe. This is done to trick the victim into thinking that the attached file is harmless. Of course, once opened, such files start a command prompt rather than Microsoft Office.

How to detect Quasar RAT using ANY.RUN?

ANY.RUN uses Suricata IDS rule sets so if malware trying to communicate with C&C servers it will be detected. To look at what threats were detected just click on the "Threats" section of the "Network" tab.

quasar network threats Figure 3: Quasar network threats

Conclusion

Quasar trojan is a powerful open-source malware equipped with a robust persistence mechanism and a complete feature set of malicious capabilities. Being available to anybody with programming knowledge, Quasar became a widely used RAT which was even featured in an attack targeted at the American government.

However, unlike other more advanced Trojans, Quasar RAT does not have extremely sophisticated anti-analysis features, which makes setting up robust cyber-defense an easier task, especially when using malware hunting services like ANY.RUN to simplify and streamline the research process.

IOCs

IP addresses
193.161.193.99
66.254.114.41
103.99.1.128
208.95.112.1
3.136.65.236
3.22.15.135
3.134.39.220
3.134.125.175
3.14.182.203
3.17.7.232
52.14.18.129
104.31.255.10
104.31.254.10
172.67.75.176
3.13.191.225
3.22.30.40
51.81.241.89
92.222.72.160
173.170.111.212
156.218.123.153
Hashes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harold.jetos.com
2.tcp.ngrok.io
marsachant.ddns.net
severdops.ddns.net
isns.net
4.tcp.ngrok.io
majul.com
news.shangrilaexports.com
cthree.msoftupdates.com
ctwo.msoftupdates.com
cone.msoftupdates.com
05eca2b70a29.ngrok.io
a234b459b6e0.ngrok.io
a234b459b6e0.ngrok.io
28e8ad52aeaf.ngrok.io
bbcadd17adea.ngrok.io
d6e52dc32552.ngrok.io
ac44c74bafd5.ngrok.io
3ee6f20d23fb.ngrok.io
29eb5becd65d.ngrok.io

HAVE A LOOK AT

Adwind screenshot
Adwind
adwind trojan
Adwind RAT, sometimes also called Unrecom, Sockrat, Frutas, jRat and JSocket is a Malware As A Service Remote Access Trojan that attackers can use to collect information from infected machines. It was one of the most popular RATs in the market in 2015.
Read More
Agent Tesla screenshot
Agent Tesla
agenttesla trojan rat stealer
Agent Tesla is spyware that collects information about the actions of its victims by recording keystrokes and user interactions. It is falsely marketed as a legitimate software on the dedicated website where this malware is sold.
Read More
Ave Maria screenshot
Ave Maria
avemaria stealer trojan rat
Ave Maria malware is a Remote Access Trojan that is also called WARZONE RAT. Hackers use it to control PCs of their victims remotely and steal information from infected PCs. For example, they can remotely activate the camera to take pictures of a victim and send them to a control server
Read More
Azorult screenshot
Azorult
azorult trojan rat
AZORult can steal banking information including passwords and credit card details as well as cryptocurrency. This constantly updated information stealer malware should not be taken lightly, as it continues to be an active threat.
Read More
Crimson RAT screenshot
Crimson RAT
crimson rat trojan
Crimson is a Remote Access Trojan — a malware that is used to take remote control of infected systems and steal data. This particular RAT is known to be used by a Pakistani founded cybergang that targets Indian military objects to steal sensitive information.
Read More
Danabot screenshot
Danabot
danabot trojan stealer
Danabot is an advanced banking Trojan malware that was designed to steal financial information from victims. Out of the Trojans in the wild this is one of the most advanced thanks to the modular design and a complex delivery method.
Read More