Current Injection Attack against the KLJN Secure Key Exchange
This addresses security vulnerabilities in the KLJN key exchange system, which is used for secure communication, but the work is incremental as it builds on existing methods to enhance a specific attack scenario.
The paper tackled the vulnerability of the Kirchhoff-law-Johnson-noise (KLJN) secure key exchange system to current injection attacks by simulating these attacks using LTSPICE. It showed that two security enhancement techniques—instantaneous voltage/current comparison and a simple privacy amplification scheme—effectively eliminate information leaks and preserve unconditional security.
The Kirchhoff-law-Johnson-noise (KLJN) scheme is a statistical/physical secure key exchange system based on the laws of classical statistical physics to provide unconditional security. We used the LTSPICE industrial cable and circuit simulator to emulate one of the major active (invasive) attacks, the current injection attack, against the ideal and a practical KLJN system, respectively. We show that two security enhancement techniques, namely, the instantaneous voltage/current comparison method, and a simple privacy amplification scheme, independently and effectively eliminate the information leak and successfully preserve the system's unconditional security.