The Eleventh Conference on Security and Cryptography for Networks (SCN 2018) aims to bring together researchers in the field of cryptography and information security, practitioners, developers, and users to foster cooperation, exchange techniques, tools, experiences and ideas. The conference seeks submissions from academia, government, and industry presenting novel research on all practical and theoretical aspects of cryptography and information security. The primary focus is on original, high quality, unpublished research of theoretical and practical impact, including concepts, techniques, applications and practical experiences. Submitted papers must not substantially overlap with papers that have been published or that are simultaneously submitted to a journal or a conference/workshop with proceedings.