Trojan

A trojan is harmful software that pretends to be a useful app or file, so you install it yourself and let it in.

Trojan: A trojan, named after the wooden horse, is malware disguised as something useful or fun. You install it willingly, thinking it is a game, a photo editor, a wedding card or a bank app. Once inside, it carries out hidden harmful tasks like stealing data or opening a back door.

Many Indian trojans spread as APK files in WhatsApp groups with names like RTO challan, PM scheme, free recharge or invitation card. They ask for many permissions, often SMS and accessibility, and then read OTPs or tap buttons on your behalf. Some banking trojans show a fake login page over the real bank app. Scammers may even forward the file from a hacked contact's account, which makes it feel familiar and safe.

A trojan cannot spread without your action, so the strongest defence is caution. Install only from Google Play, read what permissions an app asks for, and distrust any app that arrives as a file. If one is installed by mistake, turn on airplane mode, uninstall it and change your bank passwords. A short pause before tapping can save your whole account balance.

Tips

• Never open an APK sent on WhatsApp, even from a known contact whose account may be hacked.
• Refuse apps that ask for SMS and accessibility permission without a clear reason.
• If you installed a suspicious app, switch off data, uninstall it and call your bank using the number on your card.

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