June 2024

McAfee researchers discovered a complex Android rootkit campaign, dubbed Operation NoVoice, that infiltrated 50 applications on Google Play, exploiting vulnerabilities in the kernel that had been patched but not uninstalled. The malware was resilient enough to survive factory resets and was concealed within seemingly benign apps, which collectively garnered 2.3 million downloads. The malicious payload was hidden in the com.facebook.utils package and used steganography to embed an encrypted payload within a PNG image. The malware conducted multiple checks to avoid detection and established contact with a command-and-control server, polling for exploit packages every 60 seconds. It utilized 22 distinct exploits, including vulnerabilities that had received patches between 2016 and 2021. The malware disabled SELinux enforcement and installed a persistent rootkit that could survive factory resets. Google confirmed the removal of the infected apps but noted that users who had already downloaded them remained at risk, especially if their devices were running unpatched Android versions. McAfee advised affected users to treat their devices as compromised and consider professional inspection or hardware-level storage wiping for remediation.