Malware still in my phone even after factory reset

Understanding Persistent Malware-Like Issues on Smartphones: A Case Study and Recommended Actions

Introduction

In the realm of mobile security, users often encounter anomalies that evoke concern about potential malware infections. Despite standard security measures such as factory resets and antivirus scans, some issues persist, leading to confusion and insecurity. This article explores such a scenario—examining a user’s experience with unidentified data usage spikes and app behavior on a Samsung device—and offers guidance on how to address similar challenges effectively.

Case Overview

A user, after purchasing a Samsung smartphone, adopted heightened vigilance regarding device security. Over time, they monitored their applications and performed periodic security scans. Approximately a month ago, they observed an unexpected data usage activity attributed to an elusive app identified as “11504.” This application’s presence raised suspicion of spyware behavior, particularly regarding message tracking.

Challenges Encountered

1. Hidden App Presence: The application appeared solely in data usage metrics but was absent from the device’s application list. This discrepancy complicated efforts to disable or remove the app manually.

2. Antivirus Limitations: Standard security tools such as Bitdefender and Malwarebytes failed to detect or flag “11504” during scans, leading to uncertainty about the app’s legitimacy and threat level.

3. Data Usage Anomalies: The app’s data consumption increased from approximately 2 MB to 3 MB over a month, implying ongoing activity despite user efforts to prevent it.

4. Persistent Reappearance Post-Reset: A factory reset was performed in an attempt to eliminate the app. However, the app reappeared shortly after setup, even without browsing or installing additional applications, suggesting a deeper issue.

Analysis and Considerations

The persistent nature of “11504,” its concealment from standard app lists, and its data activity raise questions about its origin and behavior:

• Could this be a form of sophisticated spyware designed to evade detection?
• Is it possible that it is a system component or legitimate service that is misinterpreted as malicious?
• Are antivirus tools insufficiently comprehensive for such hidden or advanced persistent threats?

Recommendations for Users Facing Similar Situations

1. Use Advanced Security Tools: Consider employing specialized security solutions capable of detecting rootkits or low-level system modifications.

2. Complete System Reinstallation: If possible, perform a re-flash of the device firmware using official tools to ensure all malicious components are eradicated.

3. Review Installed Applications: Verify all apps for legitimacy, especially those with powerful permissions or unusual behavior.

4. Monitor Data Usage R