Manish Mimani, founder and CEO of Protectt.ai For years, static passwords, dynamic One-time Passwords (OTPs), and Multi-factor Authentication (MFA) have been the foundation of mobile app security. They have helped users verify their identities and kept unauthorized access at bay. But today, that’s no longer enough. Modern fraudsters aren’t just trying to break through login screens — they are targeting what happens after you log in. Post-authentication fraud is rising at an alarming pace across mobile-first industries like BFSI, fintech, and digital commerce. Fraudsters bypass identity checks altogether by compromising runtime environments, targeting APIs, or exploiting device vulnerabilities, often without ever touching credentials. The biggest misconception in mobile app security today is: If the login is secure, the app is secure. That couldn’t be further from the truth!

Mobile App Security Risks Don’t Stop at Login

Runtime Blind Spots: Once users log in, most apps assume the environment is safe. It is not.

• Malware, repackaged apps, and overlay attacks exploit runtime weaknesses.
• Fraudsters hijack active sessions and execute transactions from within.

Compromised Devices: A secure app on a rooted or jailbroken device is vulnerable.

• Malicious keyboard overlays, screen sharing, and unsafe environments open hidden backdoors.

Unsecured APIs: Many fraudsters bypass the UI entirely.

• Weak APIs are prime targets for token replay, man-in-the-middle exploits, and automated fraud.

Result: Fraud happens after successful authentication — where most defences do not exist.

The Solution: Build Defence Inside the App

To counter post-authentication threats, security must be intrinsic; not just guard the login. Embed Protection with Runtime Application Self-Protection (RASP)

• RASP sits inside the application, detecting and blocking malicious activity the moment it occurs.
• It thwarts tampering, reverse engineering, overlay attacks, and session hijacking in real time.
• Unlike static perimeter defences, RASP protects every user interaction across any network, device, or location. It transforms your app from a passive target into an active shield.

Enforce Continuous Device Integrity

• Validate the trustworthiness of the device at every step.
• Detect rooted or jailbroken devices, malicious tools, or unsafe conditions.
• Apply adaptive responses — restrict high-risk functions or block sensitive actions entirely.

Secure the API Layer End-to-End

• Treat APIs as critical attack surfaces.
• Harden with encryption, authentication, behavioural monitoring, and anomaly detection.
• Stop fraud before it can bypass the UI.

Authentication Is Just the Start Login protection is necessary, but no longer sufficient. True mobile app security is layered:

• RASP for in-app runtime defence.
• Device Integrity for trusted environments.
• API Protection for invisible attack surfaces.

Fraudsters have evolved. Thus, security must be built inside, not just around. The challenge is no longer just about the OTP; it is also about what happens after the OTP is validated. For mobile-first industries like BFSI, fintech, and digital commerce, the mobile app security of their business empires depends entirely on this strategic shift. Authentication starts the journey; RASP ensures protection every step of the way.