The presence of mobile devices has increased in our lives offering almost the same functionality as a personal computer. Android devices have appeared lately and, since then, the number of applications available for this operating system has increased exponentially. Google already has its Android Market where applications are offered and, as happens with every popular media, is prone to misuse. In fact, malware writers insert malicious applications into this market, but also among other alternative markets. Therefore, in this paper, we present PUMA, a new method for detecting malicious Android applications through machine-learning techniques by analysing the extracted permissions from the application itself.