Preventing Backdoors In Server Applications With A Separated Software Architecture (Short Paper)

Felix Schuster, Stefan Rüster, Thorsten Holz

10th Con­fe­rence on De­tec­tion of In­tru­si­ons and Mal­wa­re & Vul­nerabi­li­ty As­sess­ment (DIMVA), Berlin, July 2013


We often rely on system components implemented by potentially untrusted parties. This implies the risk of backdoors, i.e., hidden mechanisms that elevate the privileges of an unauthenticated adversary or execute other malicious actions on certain triggers. Hardware backdoors have received some attention lately and we address in this paper the risk of software backdoors. We present a design approach for server applications that can – under certain assumptions – protect against software backdoors aiming at privilege escalation. We have implemented a proof-of-concept FTP server to demonstrate the practical feasibility of our approach.


tags: backdoors, privilege separation, software security