Malicious code attacks pose a serious threat to the security of information systems, as malware evolved from innocuous conceptual software to advanced and destructive cyber weapons. However, there is still the lack of a comprehensive and useful taxonomy to classify malware according to their behavior, since commonly used names are obsolete and unable to handle the complex and multipurpose currently observed samples. In this article, we present a brief survey on available malware taxonomies, discuss about issues on existing naming schemes and introduce an extensible taxonomy consisting of an initial set of behaviors usually exhibited by malware during an infection. The main goal of our proposed taxonomy is to address the menace of potentially malicious programs based on their observed behaviors, thus aiding in incident response procedures. Finally, we present a case study to evaluate our behavior-centric taxonomy, in which we apply identification patterns extracted from the proposed taxonomy to over 12 thousand known malware samples. The leveraged results show that it is possible to screen malicious programs that exhibit suspicious behaviors, even when they remain undetected by antivirus tools.5810 27582777