Abstract:
In a traditional non-virtualized computer system the
whole software stack is highly vulnerable to security breaches.
This is mainly caused by the coexistence of deployed security
systems in the same space as the potentially compromised
operating system and applications that often run with administrative privileges. In such a structure, compromising, bypassing,
disabling, or even subverting deployed security systems become
trivial. Machine virtualization provides a powerful abstraction
for addressing information security issues. Its isolation, encapsulation, and partitioning properties can be leveraged to reduce
computer systems’ susceptibility to security breaches. This paper
demonstrates that machine virtualization when employed and
synthesized with cryptography would preserve information confidentiality even in an untrusted machine. It presents a novel information security approach called Virtualized Anti-Information
Leakage (VAIL). Its objective is to thwart malicious software
and insiders’ information leakage attacks on sensitive files after
decryption in potentially compromised computer systems. VAIL’s
defenses are evaluated against a variety of information leakage
attacks including: (1) direct attacks launched on sensitive files
from an untrusted virtual machine, and a compromised virtual
machine monitor; and (2) indirect attacks exploiting covert
storage and timing channels. Based on the security evaluation,
it is concluded that VAIL effectively complied with the security
requirements, and met its objective.