Global ISR: Toward a Comprehensive Defense Against Unauthorized Code Execution

Abstract

Abstract. Instruction-set randomization (ISR) obfuscates the "language" understood by a system to protect against code-injection attacks by presenting an ever-changing target. ISR was originally motivated by code injection through buffer overflow vulnerabilities. However, Stuxnet demonstrated that attackers can exploit other vectors to place malicious binaries into a victim's filesystem and successfully launch them, bypassing most mechanisms proposed to counter buffer overflows. We propose the holistic adoption of ISR across the software stack, preventing the execution of unauthorized binaries and scripts regardless of their origin. Our approach requires that programs be randomized with different keys during a user-controlled installation, effectively combining the benefits of code whitelisting/signing and runtime program integrity. We discuss how an ISR-enabled environment for binaries can be implemented with little overhead in hardware, and show that higher-overhead softwareonly alternatives are possible. We use Perl and SQL to demonstrate the application of ISR in scripting environments with negligible overhead.

Towards a Theory of Moving Target Defense

“…Most of the previous work focuses on specific aspects of system configuration, such as IP addresses [10,2,8], memory layouts [27,15], instruction sets [13,4], html keywords [28,7], SQL queries [5], database table keywords [7], etc. Recently a few comprehensive frameworks [20,14] have been proposed, but most are still conceptual and require significant theoretical and practical effort to bring them to fruition.…”

Toward Proactive, Adaptive Defense: A Survey on Moving Target Defense

“…• What to move: 'What to move' refers to what system configuration attribute (i.e., attack surface) can be dynamically changed to confuse attackers. The example system or network attributes that can be changed include instruction sets [86,123], address space layouts [135], IP addresses [3,10,79,88,138], port numbers [97], proxies [83], virtual machines [165,20], operating systems [148], or software programs [76]. Table III summarizes the moving elements by MTD techniques in different system layers [4,69].…”

Numerical SQL Value Expressions Over Encrypted Cloud Databases

“…Or, since, wisely in these troubled times, the code, with its run-time variables, is protected, e.g. by a moving target defense like [11]. We recall that these recent techniques aim on secure cloud software through secret randomization of the code and variables, blocking injections and reverse engineering.…”

“…Such hope was probably unreasonable in the past. The progress in secure software engineering, e.g., through the moving target defenses, [11], makes it henceforward rational.…”