USENIX Security Paper
Our results were published in the 27th USENIX Security Symposium:
Abstract
The Public Key Infrastructure (PKI) protects users from malicious man-in-the-middle attacks by having trusted Certificate Authorities (CAs) vouch for the domain names of servers on the Internet through digitally signed certificates. Ironically, the mechanism CAs use to issue certificates is itself vulnerable to man-in-the-middle attacks by network-level adversaries. Autonomous Systems (ASes) can exploit vulnerabilities in the Border Gateway Protocol (BGP) to hijack traffic destined to a victim's domain. In this paper, we rigorously analyze attacks that an adversary can use to obtain a bogus certificate. We perform the first real-world demonstration of BGP attacks to obtain bogus certificates from top CAs in an ethical manner. To assess the vulnerability of the PKI, we collect a dataset of 1.8 million certificates and find that an adversary would be capable of gaining a bogus certificate for the vast majority of domains. Finally, we propose and evaluate two countermeasures to secure the PKI: 1) CAs verifying domains from multiple vantage points to make it harder to launch a successful attack, and 2) a BGP monitoring system for CAs to detect suspicious BGP routes and delay certificate issuance to give network operators time to react to BGP attacks.
The full publication is available here.
Click here to view the presentation slides and here to download the presentation audio.
More information is also available on the USENIX website.
Watch our presentation from USENIX Security: