User-Level Infrastructure for System Call Interposition: A Platform for Intrusion Detection and Confinement K. Jain R. Sekar Iowa State University State University of New York Ames, IA 50014 Stony Brook, NY 11794
[email protected] [email protected] Abstract attacks launched remotely via the Internet. Such attacks may utilize a variety of techniques, e.g., exploit software er- Several new approaches for detecting malicious attacks rors in privileged programs to gain root privilege, exploit on computer systems and/or confining untrusted or ma- vulnerabilities in system configuration to access confiden- licious applications have emerged over the past several tial data, or rely on a legitimate system user to download years. These techniques often rely on the fact that when and run a legitimate-looking Trojan Horse program that in- a system is attacked from a remote location over a network, flicts damage. Intrusion detection refers to a broad range of damage can ultimately be inflicted only via system calls techniques that have been developed over the past several made by processes running on the target system. This factor years to protect against malicious attacks. A majority of has lead to a surge of interest in developing infrastructures these techniques take the passive approach of offline moni- that enable secure interception and modification of system toring of system (or user) activities to identify those activ- calls made by processes running on the target system. Most ities that deviate from the norm [1, 26, 10, 12, 17, 21] or known approaches for solving this problem have relied on are otherwise indicative of attacks [14, 18, 22].