An Android Security Extension to Protect Personal Information against Illegal Accesses and Privilege Escalation Attacks

Recently, it is widespread for malware to collect sensitive information owned by third-party applications as well as to escalate its privilege to the system level (the highest level) on the Android platform. An attack of obtaining root-level privilege in an Android environment can form a serious threat to users from the viewpoint of breaking down the whole security system. This paper proposes a new scheme that effectively prevents privilege escalation attacks and protects users’ personal information in Android. Our proposed scheme can detect and respond to malware that illegally acquires rootlevel privilege using pWhitelist, a list of trusted programs with root-level permission. Moreover, the scheme does not permit even a privileged program to access users’ personal information based on the principle of least privilege. As a result, it protects personal information against illegal accesses by malicious applications even though they illegally obtain root-level permissions by exploiting vulnerabilities of trusted programs.