Google actively scans for websites using nulled software. When they detect malware, your site gets flagged with a “Deceptive site ahead” warning. Your traffic drops to zero, your reputation is destroyed, and cleaning your site costs far more than a legitimate theme.
Do not use nulled OpenCart themes. The short-term savings are dwarfed by the long-term costs of security breaches, legal liability, and operational downtime. Opencart Nulled Themes
Stick to well-known free themes with active GitHub repositories and positive reviews. Avoid any theme that requires you to "disable antivirus to download." Google actively scans for websites using nulled software