Trojans

In short: A trojan is malware that disguises itself as a useful program and carries out harmful functions in the background.

In more detail: The name comes from the Trojan horse. Unlike viruses or worms, a trojan does not replicate itself; the user installs it voluntarily because they think it is harmless.

In Depth

Typical distribution

Pirated copies, fake updates, cracks, e-mail attachments, manipulated apps and infected downloads.

Types

Backdoor trojans, banking trojans, downloader trojans, infostealer trojans, keyloggers, ransomware droppers and the AIDS trojan as the ancestor.

Protection

Software only from official sources, up-to-date antivirus (anti-malware), user account without administrator rights, scepticism towards free cracks.

See also: Malware, Backdoor Trojan, Banking Trojan, Keylogger