Biblio
There have been many research efforts on detecting vulnerability such as model checking and formal method. However, according to Rice's theorem, checking whether a program contains vulnerable code by static checking is undecidable in general. In this paper, we propose a method of attack surface reduction using enumeration of call graph. Proposal system is divided into two steps: enumerating edge E[Function Fi, Function Fi+1] and constructing call graph by recursive search of [E1, E2, En]. Proposed method enables us to find the sum of paths of which leaf node is vulnerable function VF. Also, root node RF of call graph is part of program which is open to attacker. Therefore, call graph [VF, RF] can be eliminated according the situation where the program is running. We apply proposal method to the real programs (Xen) and extracts the attack surface of CVE-2013-4371. These vulnerabilities are classified into two class: use-after-free and assertion failure. Also, numerical result is shown in searching attack surface of Xen with different search depth of constructing call graph.
Virtualization technology has become ubiquitous in the computing world. With it, a number of security concerns have been amplified as users run adjacently on a single host. In order to prevent attacks from both internal and external sources, the networking of such systems must be secured. Network intrusion detection systems (NIDSs) are an important tool for aiding this effort. These systems work by analyzing flow or packet information to determine malicious intent. However, it is difficult to implement a NIDS on a virtualized system due to their complexity. This is especially true for the Xen hypervisor: Xen has incredible heterogeneity when it comes to implementation, making a generic solution difficult. In this paper, we analyze the network data flow of a typical Xen implementation along with identifying features common to any implementation. We then explore the benefits of placing security checks along the data flow and promote a solution within the hypervisor itself.
This research focuses on hyper visor security from holistic perspective. It centers on hyper visor architecture - the organization of the various subsystems which collectively compromise a virtualization platform. It holds that the path to a secure hyper visor begins with a big-picture focus on architecture. Unfortunately, little research has been conducted with this perspective. This study investigates the impact of monolithic and micro kernel hyper visor architectures on the size and scope of the attack surface. Six architectural features are compared: management API, monitoring interface, hyper calls, interrupts, networking, and I/O. These subsystems are core hyper visor components which could be used as attack vectors. Specific examples and three leading hyper visor platforms are referenced (ESXi for monolithic architecture; Xen and Hyper-V for micro architecture). The results describe the relative strengths and vulnerabilities of both types of architectures. It is concluded that neither design is more secure, since both incorporate security tradeoffs in core processes.