What are common email-based malware types (Trojans, ransomware, worms)?

Trojans disguise as legitimate files, providing backdoor access when executed. Email trojans often pose as invoices, shipping notices, or documents. Once running, they enable persistent attacker access to compromised systems.

Ransomware encrypts victim files and demands payment for decryption. Email delivery typically uses malicious attachments or links. Ransomware attacks cause significant business disruption and financial loss.

Worms spread automatically through contact lists once installed. Email worms send themselves to all contacts, multiplying rapidly. While less common now due to filtering improvements, worms still pose organizational risk.