Protecting Drive Encryption Systems Against Memory Attacks

Software drive encryption systems are vulnerable to memory attacks, in which an attacker gains physical accesses to the unattended computer, obtains the decryption keys from memory and consequently decrypts the drive. We reviewed the currently existing mitigations and have found that they provide only partial protection, and none of them protect against the full range of memory attacks. We propose a new method for protecting encryption systems against memory attacks, by converting them to use two tiers of keys, a single Master Key and a set of File or Sector keys. When the computer is unattended, the Master Key and part of the second-tier keys are erased from memory. The method is secure against any type of memory attack, including attackers who gain complete control of the unattended system. Compared to previous methods of protection, which erase keys and shut down the computer, our method allows to keep the computer operational by a combination of cryptographic and operating systems...

• Type: Journal
• Year: 2011
• Where: IACR
• Authors: Leo Dorrendorf
• Keywords: Decryption Keys, Drive Encryption, Encryption Systems, IACR 2011