Class: Backdoor
Backdoors are designed to give malicious users remote control over an infected computer. In terms of functionality, Backdoors are similar to many administration systems designed and distributed by software developers. These types of malicious programs make it possible to do anything the author wants on the infected computer: send and receive files, launch files or delete them, display messages, delete data, reboot the computer, etc. The programs in this category are often used in order to unite a group of victim computers and form a botnet or zombie network. This gives malicious users centralized control over an army of infected computers which can then be used for criminal purposes. There is also a group of Backdoors which are capable of spreading via networks and infecting other computers as Net-Worms do. The difference is that such Backdoors do not spread automatically (as Net-Worms do), but only upon a special “command” from the malicious user that controls them.Read more
Platform: MSIL
The Common Intermediate Language (formerly known as Microsoft Intermediate Language, or MSIL) is an intermediate language developed by Microsoft for the .NET Framework. CIL code is generated by all Microsoft .NET compilers in Microsoft Visual Studio (Visual Basic .NET, Visual C++, Visual C#, and others).Family: Backdoor.MSIL.AsyncRat
No family descriptionExamples
580BEEFFCCADDB22294A6DD53ABA466ETactics and Techniques: Mitre*
TA0005
Defense Evasion
The adversary is trying to avoid being detected. Defense Evasion consists of techniques that adversaries use to avoid detection throughout their compromise. Techniques used for defense evasion include uninstalling/disabling security software or obfuscating/encrypting data and scripts. Adversaries also leverage and abuse trusted processes to hide and masquerade their malware. Other tactics' techniques are cross-listed here when those techniques include the added benefit of subverting defenses.
T1562.001
Disable or Modify Tools
Adversaries may modify and/or disable security tools to avoid possible detection of their malware/tools and activities. This may take many forms, such as killing security software processes or services, modifying / deleting Registry keys or configuration files so that tools do not operate properly, or other methods to interfere with security tools scanning or reporting information. Adversaries may also disable updates to prevent the latest security patches from reaching tools on victim systems.
TA0011
Command and Control
The adversary is trying to communicate with compromised systems to control them. Command and Control consists of techniques that adversaries may use to communicate with systems under their control within a victim network. Adversaries commonly attempt to mimic normal, expected traffic to avoid detection. There are many ways an adversary can establish command and control with various levels of stealth depending on the victim's network structure and defenses.
T1071.001
Web Protocols
Adversaries may communicate using application layer protocols associated with web traffic to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server.
T1571
Non-Standard Port
Adversaries may communicate using a protocol and port pairing that are typically not associated. For example, HTTPS over port 8088 or port 587 as opposed to the traditional port 443. Adversaries may make changes to the standard port used by a protocol to bypass filtering or muddle analysis/parsing of network data.
* © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation.