A loader is malicious software that infiltrates devices to deliver malicious payloads. This malware is capable of infecting victims’ computers, analyzing their system information, and installing other types of threats, such as trojans or stealers. Criminals usually deliver loaders through phishing emails and links by relying on social engineering to trick users into downloading and running their executables. Loaders employ advanced evasion and persistence tactics to avoid detection.

First identified in March 2021, PureCrypter is a .NET-based loader that employs obfuscation techniques, such as SmartAssembly, to evade detection. It has been used to distribute malware families including AgentTesla, RedLine Stealer, and SnakeKeylogger. The malware is typically delivered through phishing campaigns and malicious downloads, often masquerading as legitimate files with extensions like .mp4 or .pdf. PureCrypter utilizes encryption and compression to conceal its payloads and can inject malicious code into legitimate processes to maintain persistence on the infected system.

The main function of Smoke Loader is dropping other, more destructive malware on infected machines. However, unlike many competing loaders, this one can be extended via plugins to feature destructive, malicious info-stealing functions.

Stealers are a group of malicious software that are intended for gaining unauthorized access to users’ information and transferring it to the attacker. The stealer malware category includes various types of programs that focus on their particular kind of data, including files, passwords, and cryptocurrency. Stealers are capable of spying on their targets by recording their keystrokes and taking screenshots. This type of malware is primarily distributed as part of phishing campaigns.