Cyber Security Expert & CEO Netchange AG Mathias Gut is a cyber security expert who works daily to promote security in the digital world. He is a founding member and co-owner of Netchange, a company founded in 2001 that specializes in practical cyber security solutions, cyber security consulting, and cyber security audits. His daily tasks in the field of cyber security include consulting and audits, training specialists, and offensive security testing, particularly using OSINT and red teaming. He places particular emphasis on practical solutions. Mathias Gut is co-author of the book CompTIA Security+ - IT Security Explained, published by mitp Verlag. In his spare time, he develops open source security tools and is a core developer of an exposure and attack surface monitor. His profile is rounded off by his many years of teaching experience with a focus on cyber security.