Glossary - Learn more about malware - Microsoft Malware Protection Center

 

ActiveX Control
A software component of Microsoft Windows that can be used to create and distribute small applications through Internet Explorer. ActiveX controls can be developed and used by software to perform functions that would otherwise not be available using normal Internet Explorer capabilities. Because ActiveX controls can be used to perform a wide variety of functions, including downloading and running programs, vulnerabilities discovered in them may be exploited by malware. In addition, cybercriminals may also develop their own ActiveX controls, which can do damage to a computer if a user visits a webpage that contains the malicious ActiveX control.

Adware
A program that displays advertisements. While some adware can be beneficial by subsidizing a program or service, other adware programs may display advertisements without adequate consent.

Alert Level
An alert level is assigned to particular malware by an analyst when adding detection. It is based on a calculation that takes into account the malware's ability to spread and potential to cause damage. The different alert levels used by Windows Defender are explained here.

Alias
An alternative detection for particular malware. Generally this refers to detections of the same malware by other antivirus vendors; however, it may also refer to an alternative Microsoft detection of the same malware. For rogue software, this may refer to the name it uses for its fake antivirus program.

API
Stands for "Application Programming Interface". A set of routines that an application uses to interface to lower-level services. APIs allow standard access to low-level programming functions, separating high-level programs from the need to understand the low-level programming required for each piece of hardware or service.

B

Backdoor Trojan
A type of trojan that provides attackers with remote unauthorized access and control of infected computers. Bots are a subcategory of backdoor trojans (see botnet).

Glossary - Learn more about malware - Microsoft Malware Protection Center