Worm

Security+ 🏆 • Threats ⚠️ • Network Attacks 🎯 Difficulty: free

Definition

A worm is a type of malware that can self-replicate and spread automatically from one system to another, usually by exploiting vulnerabilities or weak configurations. Worms can spread rapidly across networks without requiring a user to open a file, which can lead to widespread disruption in a short time.

Examples

  • A worm exploits an unpatched service on Windows hosts and spreads across the internal network within minutes.
  • A worm uses stolen credentials to copy itself to shared network folders and execute remotely.

Discover 🔎

Some malware needs users to click or install it. Worms are different. A worm can spread on its own, moving from system to system automatically. That ability to self-propagate is what makes worms so dangerous. If conditions are right, a worm can cause an outbreak that impacts large parts of a network very quickly.

Remember: A worm spreads itself. It does not rely on a user repeatedly opening the same file to move to the next system.
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