Malware

Sec+ Glossary 📖 • Threats ⚠️ • Security+ 02 Difficulty: free

What is Malware?

Malware is malicious software designed to harm systems, steal data, disrupt operations, or gain unauthorized access. It can infect devices through phishing, unsafe downloads, vulnerabilities, or compromised credentials, and it often tries to remain hidden while carrying out its goal.

Examples

  • A user opens a fake invoice attachment and unknowingly installs malware that steals saved browser passwords.
  • A ransomware infection encrypts files on a shared drive and demands payment for decryption.

Discover 🔎

Malware is one of the most common threats in cybersecurity because it is flexible. Attackers can use malware to steal data, spy on users, lock systems for ransom, or quietly gain long-term access. Malware is not a single thing. It is a broad category of harmful software, and understanding the common types helps you recognize how attacks work and what defenses matter most.

Remember: Malware is software with malicious intent. The same delivery method, like phishing, can lead to many different malware outcomes depending on what the attacker wants.

Summary 📝

Malware is malicious software used to steal, disrupt, or gain unauthorized access. Common types include viruses, worms, trojans, ransomware, spyware, rootkits, and bots. Malware often enters through phishing, unsafe downloads, or unpatched vulnerabilities, and it may try to persist and remain hidden. Effective defense combines patching, least privilege, endpoint protection, monitoring, and strong backup and recovery.

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