This document is an internship report submitted by Rihab Chebbah to the Ministry of Higher Education and Scientific Research after completing a summer internship at LEONI Tunisia from June 1-30, 2016. The report includes an acknowledgements section thanking her advisors. It then provides an introduction to the topic of application security auditing, which was the focus of her internship project. The first chapter presents information about LEONI Tunisia and the Information Management department where she completed her internship.