Cybercriminals are using Microsoft’s .NET MAUI framework to create advanced Android malware that bypasses security measures and compromises user data. A study by McAfee researchers highlights a rise in malicious apps developed with this tool since its introduction in May 2022. These apps often impersonate legitimate applications, particularly from financial institutions, and are distributed through third-party websites or alternative app stores. One example is a counterfeit app mimicking the official IndusInd Bank app, targeting users in India to extract sensitive information. Another variant targets Chinese-speaking users by disguising itself as a social networking service.
The malicious apps are designed to be subtle, with harmful code concealed as blob files within the assemblies directory, making detection difficult for antivirus solutions. Hackers use multi-stage dynamic loading, where the Android executable file is loaded in three stages, each encrypted until execution. They also manipulate the AndroidManifest.xml file by adding excessive permissions, complicating analysis and detection. Additionally, attackers replace standard HTTP requests with encrypted TCP socket connections to evade security software. These evolving tactics indicate a potential increase in similar mobile malware threats in the future.