Inno Setup is a legitimate Windows installer framework used to package and deploy software. It can copy files, write registry keys, create shortcuts, and run scripts or commands during installation. Because those actions are normal for a setup program, attackers sometimes abuse Inno Setup to make malware look like ordinary software and to launch hidden payloads after the user starts the installer.
This matters in cyber security because a signed-looking or familiar installer can bypass user suspicion and blend into normal IT activity. In real attacks, an Inno Setup package may drop additional files, execute a second-stage loader, or contact remote servers after installation. Defenders often treat installers as executable code, not documents: they inspect filenames and hashes, sandbox the setup, watch for unexpected child processes, and monitor outbound connections. Unexpected use of an installer framework is a strong indicator that trusted packaging is being used as a delivery mechanism rather than for legitimate deployment.