DeepSec 2016 Talk: Systematic Fuzzing and Testing of TLS Libraries – Juraj Somorovsky

Sanna/ November 8, 2016/ Conference, Development, Security

In his talk Juraj Somorovsky presents TLS-Attacker, a novel framework for evaluating the security of TLS libraries. Using a simple interface, TLS-Attacker allows security engineers to create custom TLS message flows and arbitrarily modify TLS message contents in order to test the behavior of their TLS libraries. Based on TLS-Attacker, he and his team first developed a two-stage TLS fuzzing approach. This approach automatically searches for cryptographic failures and boundary violation vulnerabilities. It allowed him to find unusual padding oracle vulnerabilities and overflows/overreads in widely used TLS libraries, including OpenSSL, Botan, and MatrixSSL. Juraj’s findings encouraged the use of comprehensive test suites for the evaluation of TLS libraries, including positive as well as negative tests. He and his team used TLS-Attacker to create such a test suite framework, which finds further problems in TLS libraries. TLS-Attacker is an open source tool, and is currently being deployed for internal

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DeepSec 2016 Talk: TLS 1.3 – Lessons Learned from Implementing and Deploying the Latest Protocol – Nick Sullivan

Sanna/ October 19, 2016/ Conference, Development, Internet, Security

Version 1.3 is the latest Transport Layer Security (TLS) protocol, which allows client/server applications to communicate over the Internet in a way that is designed to prevent eavesdropping, tampering, and message forgery. TLS is the S in HTTPS. TLS was last changed in 2008, and a lot of progress has been made since then. CloudFlare will be the first company to deploy this on a wide scale. In his talk Nick Sullivan will be able to discuss the insights his team gained while implementing and deploying this protocol. Nick will explore differences between TLS 1.3 and previous versions in detail, focusing on the security improvements of the new protocol as well as some of the challenges his team faces around securely implementing new features such as 0-RTT resumption. He’ll also demonstrate an attack on the way some

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DeepSec 2016 Workshop: Deploying Secure Applications with TLS – Juraj Somorovsky

Sanna/ September 9, 2016/ Security, Training

Cryptography is all around us. It has become something like the background radiation of the networked world. We use it on a daily basis. Since nothing usually comes into existence by mistake, there must be someone responsible for deploying this crypto stuff. You are right. Software developers, mathematicians, engineers, system administrators, and many more people are involved to make encryption happen. The hard part is to get it right. The mathematics involved is hard. A lot can go wrong. This is why we have a workshop for you at DeepSec 2016! Have you (or your manager) ever wondered why your server is getting bad grades from SSL labs? Or are you interested in improving the performance of your TLS server? If you answer one of these question with “yes”, you should consider to take part in the

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Deep Sec2016 Talk: DROWN – Breaking TLS using SSLv2 – Nimrod Aviram

Sanna/ September 5, 2016/ Conference, Internet

In the past years encrypted communication has been subject to intense scrutiny by researchers. With the advent of Transport Layer Security (TLS) Internet communication via HTTP became a lot more secure. Its predecessor Secure Sockets Layer (SSL) must not be used any more. The real world has its own ideas. SSLv2 and SSLv3 is still present. Attackers can try to downgrade the TLS session by switching to insecure ciphers. When using the correct configuration, these downgrade attacks cannot happen. The question is: Are all of your devices, applications, and systems correctly configure? If you are not sure, better check again. In order to illustrate how these attacks work, we have invited Nimrod Aviram for DeepSec 2016. He will explain the inner workings of the DROWN attack. We present a novel cross-protocol attack on TLS

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DeepSec Video: illusoryTLS – Nobody But Us. Impersonate,Tamper and Exploit

René Pfeiffer/ February 15, 2016/ Conference, Internet, Security

Cryptographic backdoors are a timely topic often debated as a government matter to legislate on. At the same time, they define a space that some entities might have practically explored for intelligence purposes, regardless of the policy framework. The Web Public Key Infrastructure (PKI) we daily rely on provides an appealing target for attack. The entire X.509 PKI security architecture falls apart if a single CA certificate with a secretly embedded backdoor enters the certificate store of trusting parties. Do we have sufficient assurance that this has not happened already? Alfonso De Gregorio presented at DeepSec 2015 his findings and introduced illusoryTLS. Aptly named illusoryTLS, the entry is an instance of the Young and Yung elliptic curve asymmetric backdoor in the RSA key generation. The backdoor targets a Certification Authority public-key certificate, imported in

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