Malware authors have released a new version of the Android Loki trojan, which can now infect native Android OS libraries. Loki was one of the first instances where malware had found a way to infect devices and nestle right inside core Android operating system processes. Because Loki entangles itself deep in the Android OS files, the only way to remove the trojan is to reinstall (reflash) the entire operating system. Fortunately, just like in February, this malware is currently used to show annoying ads only.
Source: https://www.bleepingcomputer.com/news/security/loki-trojan-infects-android-libraries-and-system-process-to-get-root-privileges/