InfoShield: A Security Architecture for Protecting Information Usage in Memory

Cyber theft is a serious threat to Internet security. It is one of the ma-jor security concerns by both network service providers and Internet users. Though sensitive information can be encrypted when stored in non-volatile memory such as hard disks, for many e-commerce and network applications, sensitive information is often stored as plain-text in main memory. Documented and reported exploits facilitate an adversary stealing sensitive information from an application’s mem-ory. These exploits include illegitimate memory scan, information theft oriented buffer overow, invalid pointer manipulation, integer overow, password stealing trojans and so forth. Today’s computing system and its hardware cannot address these exploits effectively in a coherent way. This paper presents a unied and lightweight so-lution, called InfoShield, that can strengthen application protection against theft of sensitive information such as passwords, encryption keys, and other private data with a minimal performance impact. Un-like prior whole memory encryption and information ow based ef-forts, InfoShield protects the usage of information. InfoShield ensures that sensitive data are used only as dened by application seman-tics, preventing misuse of information. Comparing with prior art, InfoShield handles a broader range of information theft scenarios in a unied framework with less overhead. Evaluation using popular network client-server applications shows that InfoShield is sound for practical use and incurs little performance loss because InfoShield only protects absolute, critical sensitive information. Based on the proling results, only 0.3 % of memory accesses and 0.2 % of executed codes are affected by InfoShield. 1