A common security threat in messaging platforms is the spread of malicious APK files disguised as safe formats (e.g., “invoice.pdf.apk”). Many users, especially non-technical ones, may unknowingly download and install these files, exposing their devices to malware or scams.
WhatsApp is a primary communication tool for billions, including small businesses. Fraudsters often exploit trust in personal chats to distribute disguised files. While WhatsApp has basic file type warnings, they are often too subtle and easily ignored. A more proactive design is needed to alert, educate, and protect users without disrupting legitimate file-sharing.
Reduce cases of malware infections via disguised file sharing.
Build trust and safety reputation for WhatsApp, especially for business users.
Strike a balance between security enforcement and user freedom to share files.
Everyday WhatsApp users who are not tech-savvy and may fall for disguised APK traps.
Business users frequently exchanging files (invoices, receipts, documents).
Users in regions with high rates of cyber fraud via messaging.
How can WhatsApp detect and communicate suspicious files (APK disguised as PDF) in a way that is clear, trustworthy, and educational without creating too many false alarms?
Design the UI flow and key interactions for a feature where:
WhatsApp detects suspicious file naming/extension patterns (e.g., “.pdf.apk”).
The system flags the file before download with a clear visual warning.
Users are given safe options (cancel, learn more) instead of accidentally installing the file.
For advanced users, allow a way to proceed knowingly, but gated with friction (e.g., confirmation screens).
Include educational microcopy explaining why this file may be unsafe.
Must not overwhelm users with technical jargon (keep explanations simple).
Warnings should be visually strong but not block legitimate workflows.
Consider users with low digital literacy who may ignore subtle cues.
Should feel like a natural extension of WhatsApp’s existing design language.