Privacy in the Era of Surveillance: Lifting up the Doormat

On July 6 a technical study titled: Keys Under Doormats: Mandating Insecurity by Requiring Government Access to All Data and Communications has been published. The scientists behind this work are more than domain experts. Among the others: Steven M. Bellovin known for his work in the encrypted keys exchange; Josh Benaloh who invented the Benaloh cryptosystem; Matt Blaze who worked on cryptographic files systems; Whitfield Diffie universally known as one the pioneers of public key cryptography; Peter G. Neumann who worked on Provably Secure Operative Systems; Ronald L. Rivest who is “R” in RSA; Jeffrey I. Schiller known for being one of the creator of Kerberos and Bruce Schneier one the biggest expert in security and cryptography.

The paper investigates several aspects related to the present requests by some Governments about providing backdoors (exceptional accesses) in the cryptographic systems. Starting from the NSA’s Clipper Chip the athors dissect the implications of creating backdoored cryptosystem considering also the ethical and legal behind it. The paper focuses on three main problems that the exceptional access would create:

1. the break of the current best practises that have been deployed in the last years;

2. a system that would provide some backdoor mechanism, will be more complex and “complexity is the enemy of security” because prone to vulnerability;

3. “exceptional access would create concentrated targets that could attract bad actors” attacks will be focussed on the keystores that stores the keys for such exceptional access.

As the authors states in the conclusions the problem is still open and there are several questions to be discussed. “If law enforcement wishes to prioritize exceptional access, we suggest that they need to provide evidence to document their requirements and then develop genuine, detailed specifications for what they expect exceptional access mechanisms to do.”

References:

1. Abelson, H., Anderson, R., Bellovin, S. M., Benaloh, J., Blaze, M., Diffie, W., ... & Weitzner, D. J. (2015). Keys Under Doormats: Mandating insecurity by requiring government access to all data and communications.

2. The Risks of Mandating Backdoors in Encryption Products