How to remove Mozart malware

Mozart malware is a computer threat that uses DNS protocol to communicate with remote servers, this way evading AV detection

Mozart malware is a backdoor that was first identified by security researcher Vitali Kremez at the end of February 2020.^[1] While the virus operations are likely to be common to a backdoor (such as other privilege escalation, malware proliferation, harvesting of information, data corruption, etc.), one of its unique features lie within the communication protocol, which is transferred over a DNS instead of a regular HTTP/HTTPS.

This allows Mozart malware to evade the detection of security applications that monitor the HTTP traffic for malicious activity. Another benefit of the DNS protocol is that the commands from the attackers can be transferred via the DNS TXT records, which might induce malicious actions, such as data deletion, malicious code execution, etc.

Despite being evasive when it comes to its communications with a remote server, Mozart malware removal can be performed with multiple different anti-virus programs that detect the malicious activity of the virus.

Named after one of the greatest musicians of all time, Mozart virus is a relatively new strain that infected a few hundred people worldwide so far. It is also believed that that malware is still in development, as, during testing, the commands via the DNS were not reaching the target. 

Since Mozart malware is relatively unknown in the cybersecurity world, the first samples were caught in the wild, spreading with the help of malicious PDF attachments that include a malicious link to a .zip file. If executed, it triggers a JavaScript command, which downloads a file calc.exe and places it in the Temp subfolder.

From there, Mozart malware triggers the system infection process, which firstly creates a text file mozart.txt in the same Temporary file folder and inserts “12345” content inside. After that, the Trojan imports several files into the Startup folder, which makes it load every time the Windows system is booted.

Mozart malware is programmed to receive the following seven DNS request tasks, which would allow malware to update itself, allocate memory, check which updates were applied, and other commands:^[2]

• .getid
• .gettasks
• .gettasksize
• .gettask
• .reporttask
• .reportupdates
• .getupdates

After the necessary system changes, Mozart malware will continually query the .gettask command, although no response from the DNS server is received. There is also a chance that malicious actors behind the malware are first seeking to create a botnet before issuing Mozart malware with task execution.

While the virus is yet to be armed with malicious commands, we suggest you don't wait and remove Mozart malware from the tour computer as soon as possible. Backdoors can allow the attackers to take over the infected machine eventually, which can result in a variety of negative consequences for the victim, including money loss, other malware infection, data loss, and even identity theft.

To get rid of Mozart virus, perform a full system scan with a reputable anti-malware software that detects the threat.^[3] After malware removal, we suggest scanning the machine with FortectIntego to fix the virus damage done, or otherwise, Windows might suffer from various stability issues.

Spam email attachments – the most prevalent malware distribution method

Emails can be used to transfer all types of information – from informative messages to sophisticated and obfuscated attachments. As a general rule, threat actors behind malware often employ social engineering^[4] techniques in order to make users open the malicious file, triggering the infection chain.

There are several tactics that can be used to comprise a phishing email – these can also be targeted or sent to random users. Typically, botnets are employed to send out spam to hundreds or even thousands of others, infecting even more victims worldwide.

Luckily, implemented security measures within email provider systems scan all emails for malicious indicators, and flag them – place them into the “Junk” or “Spam” folders. In most cases, such emails are not even checked by most, preventing malware from spreading. However, threat actors are continually working on new and advanced techniques to bypass built-in scanners, so these malicious emails might also end up in your Inbox. At this point, it is up to you whether you will get infected or not – you should learn to recognize malicious email traits.

Thus, never allow a document, such as MS Office file, to run macro commands and also click on links that would automatically download and execute a file. Keep in mind that a single action (namely, a click) can initiate a set of events that will eventually plant malware on your machine. So don't do it.

It is also worth mentioning that scanning such attachments, and links with tools like Virus Total or anti-malware software can save you from malware infection as well – so make sure you have comprehensive security solutions installed on your machine at all times.

Use security software to delete Mozart Trojan from your machine

Just like many other backdoors, Mozart Trojan is targeting Windows systems exclusively and can result in privilege escalation, which means that the attackers could take over your machine completely. Besides, it may also gain root access^[5] to the PC, which would make Mozart malware removal extremely difficult. Without a doubt, such action cannot be executed manually, and an automatic removal tool should be used instead.

Additionally, because Mozart virus uses various methods to disguise itself from anti-malware software, you should access Safe Mode with Networking, as explained below, although this might not always be necessary. Then, perform a full system scan using SpyHunterCombo Cleaner, MalwarebytesMalwarebytes, or another reputable tool to remove Mozart malware from your system thoroughly.