Remote Access Trojan (RAT)

Threats ⚠️ • Security Operations 🛡️ • Sec+ Glossary 📖 Difficulty: free

What is Remote Access Trojan (RAT)?

A Remote Access Trojan, or RAT, is a type of malware that gives an attacker unauthorized remote control over an infected device.

Examples

  • An employee opens a malicious attachment, and the installed RAT allows the attacker to browse files and execute commands from another location.
  • A compromised workstation begins contacting an external command server, giving the attacker remote control over the system and access to saved data.

Discover 🔎

Some malware is designed to destroy data, some is built to steal credentials, and some exists mainly to open the door for an attacker. A Remote Access Trojan belongs to that last group. Its purpose is not simply to infect a machine and stop there. Its purpose is to give the attacker a way to operate the victim’s device from a distance.

That makes a RAT especially dangerous. Once it is active, the attacker may be able to browse files, run commands, install more malware, capture what the user types, or quietly watch the system over time. Instead of a short, obvious infection, a RAT often turns the device into a long-term foothold.

Remember: A RAT is dangerous because it gives the attacker ongoing control, not just one brief malicious action.

Summary 📝

A Remote Access Trojan is malware designed to give an attacker remote control over an infected system. Once active, it can support spying, data theft, command execution, persistence, and movement into other systems. Its real danger comes from the fact that it turns a single infected device into an ongoing attacker-controlled foothold rather than a one-time malware event.

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