A backdoor is a type of cybersecurity threat that allows attackers to secretly compromise a system and conduct malicious activities, such as stealing data and modifying files. Backdoors can be difficult to detect, as they often use legitimate system applications to evade defense mechanisms. Threat actors often utilize special malware, such as PlugX, to establish backdoors on target devices.

Spyware is a stealth form of malware whose primary objective is to gather sensitive information, such as personal data, login credentials, and financial details, by monitoring user activities and exploiting system vulnerabilities. Spyware operates secretly in the background, evading detection while transmitting collected data to cybercriminals, who can then use it for malicious purposes like identity theft, financial fraud, or espionage.