Truncating TLS Connections to Violate Beliefs in Web Applications
We identify logic flaws to: cast votes on behalf of honest voters in e-voting, take full control of Microsoft accounts, and temporary access to Google accounts.
Abstract
We identify logical web application flaws which can be exploited by TLS truncation attacks to desynchronize the user- and server-perspective of an application's state. It follows immediately that servers may make false assumptions about users, hence, the flaw constitutes a security vulnerability. Moreover, in the context of authentication systems, we exploit the vulnerability to launch the following practical attacks: we exploit the Helios electronic voting system to cast votes on behalf of honest voters, take full control of Microsoft Live accounts, and gain temporary access to Google accounts.
Acknowledgement from Google and Microsoft
Our contribution has been acknowledged in Google's Hall of Fame and Microsoft's Security Researcher Acknowledgements.
Media coverage
This article has been discussed by The Register (local cache) and Spiegel Online (local cache).
Talk and video demonstrations
Our Black Hat talk and videos demonstrating our attacks against Google, Helios and Microsoft are available on YouTube:
@inproceedings{Smyth13-truncation-attacks-to-violate-beliefs,
title = {{Truncating TLS Connections to Violate Beliefs in Web Applications}},
year = {2013}, author = {Ben Smyth and Alfredo Pironti},
url = {./},
url-pdf = {./files/truncation-attacks-to-violate-beliefs.pdf},
url-bib = {./files/truncation-attacks-to-violate-beliefs.bib},
url-yaml = {./files/truncation-attacks-to-violate-beliefs.yml},
url-md = {./files/truncation-attacks-to-violate-beliefs.md}
}