What is a worm in cybersecurity?
D2 · Threats · CompTIA Security+ SY0-701A worm is a type of malware that self-replicates and spreads automatically across networks by exploiting vulnerabilities — without requiring any user interaction or host program (unlike viruses).
Famous examples: WannaCry (2017 — used EternalBlue SMB exploit, spread ransomware globally), Stuxnet (2010 — targeted Iranian nuclear centrifuges), Morris Worm (1988 — first major internet worm).
Worms consume bandwidth and system resources, causing collateral damage even without a destructive payload.
Famous examples: WannaCry (2017 — used EternalBlue SMB exploit, spread ransomware globally), Stuxnet (2010 — targeted Iranian nuclear centrifuges), Morris Worm (1988 — first major internet worm).
Worms consume bandwidth and system resources, causing collateral damage even without a destructive payload.
Key distinction: worms spread automatically (no user action needed); viruses require execution by user/host program. WannaCry is the go-to exam example — it combined a worm (EternalBlue spreading) with ransomware payload. Patch SMB vulnerabilities (MS17-010) to prevent worm spreading.