Biblio

The widespread adoption of DEP has made most modern attacks follow the same general steps: Attackers try to construct code-reuse attacks by using vulnerable indirect branch instructions in shared objects after successful exploits on memory vulnerabilities. In response to code-reuse attacks, researchers have proposed a large number of defenses. However, most of them require access to source code and/or specific hardware features. These limitations hinder the deployment of these defenses much.In this paper, we propose an address-based code-reuse attack mitigation for shared objects at the binary-level. We emphasize that the execution of indirect branch instruction must follow several principles we propose. More specifically, we first reconstruct function boundaries at the program’s dynamic-linking stage by combining shared object’s dynamic symbols with binary-level instruction analysis. We then leverage static instrumentation to hook vulnerable indirect branch instructions to a novel target address computation and validation routine. At runtime, AddrArmor will protect against code-reuse attacks based on the computed target address.Our experimental results show that AddrArmor provides a strong line of defense against code reuse attacks, and has an acceptable performance overhead of about 6.74% on average using SPEC CPU 2006.

In monolithic operating system (OS), any error of system software can be exploit to destroy the whole system. The situation becomes much more severe in cloud environment, when the kernel and the hypervisor share the same address space. The security of guest Virtual Machines (VMs), both sensitive data and vital code, can no longer be guaranteed, once the hypervisor is compromised. Therefore, it is essential to deploy some security approaches to secure VMs, regardless of the hypervisor is safe or not. Some approaches propose microhypervisor reducing attack surface, or a new software requiring a higher privilege level than hypervisor. In this paper, we propose a novel approach, named HyperPS, which separates the fundamental and crucial privilege into a new trusted environment in order to monitor hypervisor. A pivotal condition for HyperPS is that hypervisor must not be allowed to manipulate any security-sensitive system resources, such as page tables, system control registers, interaction between VM and hypervisor as well as VM memory mapping. Besides, HyperPS proposes a trusted environment which does not rely on any higher privilege than the hypervisor. We have implemented a prototype for KVM hypervisor on x86 platform with multiple VMs running Linux. KVM with HyperPS can be applied to current commercial cloud computing industry with portability. The security analysis shows that this approach can provide effective monitoring against attacks, and the performance evaluation confirms the efficiency of HyperPS.