A disgruntled or terminated employee who steals data by introducing malware is an example of which insider type?

• A. Negligent Insider
• B. Compromised Insider
• C. Professional Insider
• D. Malicious Insider

Answer: (D)

The main concept is distinguishing insider threats by the intent and action behind the wrongdoing. A disgruntled or terminated employee who deliberately introduces malware to steal data shows intentional harm from someone with trusted access. That combination—malicious intent plus insider access—fits a Malicious Insider best. The other types describe different scenarios: a negligent insider acts carelessly without intent to steal, a compromised insider’s actions come from someone else using their credentials, and a professional insider typically refers to a role-based misuse not driven by active malicious intent. Here, the deliberate malware deployment by someone with legitimate access is the hallmark of a Malicious Insider.