Patents Pending:
Secure Bit 2 is a patent pending, Transparent, Hardware solution against Buffer-Overflow attacks on control data (return-address and function-pointer attacks in particular). It is a continuation of our original work on Secure Bit: both are based on an added Secure Bit, but the management of the bit is dramatically different. We refer to the new management scheme as Secure Bit 2. Secure Bit is a concept to provide a hardware bit to protect the integrity of addresses for the purpose of preventing buffer-overflow attacks. Secure Bit 2 is our second implementation of a protocol to manage the Secure Bit. SecureBit2 is completely transparent to software, and provides 100% backward compatible with legacy code. Unlike several methods that only reduce the probability of a successful attack, Secure Bit 2 can detect and prevent all address-corrupting buffer-overflow attacks. Secure Bit 2 is transparent to software, and has little run-time performance penalty (almost none). The goal of Secure Bit 2 is to provide hardware support to protect against current and future generations of buffer-overflow attacks by protecting the integrity of addresses: addresses passed in buffers between processes are invalid. Robustness and transparency are demonstrated by emulating the hardware, and booting Linux on the emulator, running application software on that Linux, and performing known attacks.
For details see : Piromsopa and Enbody, "Secure Bit : Transparent, Hardware Buffer-Overflow Protection," IEEE Transactions on Dependable and Secure Computing, Vol. 3, No. 4, October-December 2006.
This patent builds on the secure platform provided by Secure Bit to cover non-control data, i.e. data not covered by Secure Bit. The basic idea is to use Canary Words, but protect them with Secure Bit. Canary Words have been shown to be effective and are in use, but securing them has been complicated and not without vulnerabilities. Secure Bit provides a simple and secure method of protecting Canary Words.
Last updated November 5, 2007 15:43