In the last years, some large companies have been involved in scandals related to financial mismanagement, which represented a large financial damage to their stockholders. To recover market confidence, certifications for best practices of governance were developed, and in some cases, harder laws were implemented. Companies adhered to these changes as a response to the market, deploying process aware systems (PAS) and adopting the best practices of governance. However, companies demand a rapid response to strategic changes or changes in business models between partners, which may impose serious drawbacks to the adoption of normative PAS to the competitiveness of these companies. Thus, while companies need flexible PAS, flexibility may compromise security. To re-balance the trade-off between security and flexibility, we present in this work an anomaly detection algorithm for PAS. 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