DeepSec 2013 Video: Trusted Friend Attack – (When) Guardian Angels Strike

René Pfeiffer/ February 6, 2014/ Conference, Internet, Security, Stories

We live in a culture where everybody can have thousands of friends. Social media can catapult your online presence into celebrity status. While your circle of true friends may be smaller than your browser might suggest, there is one thing that plays a crucial role when it comes to social interaction: trust. Did you ever forget the password to your second favourite social media site? If so, how did you recover or reset it? Did it work, and were you really the one who triggered the „lost password“ process? In a world where few online contacts can meet each other it is difficult for a social media site to verify that the person requesting a new password is really the individual who holds the account. Facebook has introduced Trusted Friends to facilitate the identity

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DeepSec 2013 Talk: Risk Assessment For External Vendors

René Pfeiffer/ November 6, 2013/ Conference, Security, Stories

No man is an island. If this is true for every single one of us, then it is also true for companies. Modern enterprises have business to business (B2B) relations. They are at the centre of a network of suppliers and other vendors. Information flows between the players since they need to exchange data. What do you do if you deal with confidential or regulated data which mustn’t flow freely? How do you assess the risks? How do you determine what security measures work best? How do you deal with the situation of not enforcing security because every player runs its own policies? Luciano Ferrari has prepared a presentation for you and talks about his experience. The first issue is physical proximity. Once you are linked with business entities several thousands of miles away

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Of CAs, DLP, CSRs, MITM, inspection and compliance

René Pfeiffer/ February 16, 2012/ Discussion, Security

Writing about certificate authorities is slowly turning into beating dead horses. We have seen a couple of security breaches at CAs in the past. We have witnessed security researchers turning to SSL/TLS. Fairly recently researchers have put RSA keys to the test and found common prime factors in thousands of keys. Now we have a discussion about compliance. The Mozilla team has given CAs a stern warning sparked by the issue of a signing certificate by the Trustwave CA to a customer using a data loss prevention (DLP) device. According to a report the signing root certificate was used inside a Hardware Security Module for the purpose of dynamically creating fake certificates in order to inspect encrypted web traffic. While there was an audit at the customer’s site, this incident has sparked a heated

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Lessons in Trust and Malicious Code from the Staatstrojaner

René Pfeiffer/ October 31, 2011/ Security

Since it is Halloween we will beat an undead horse in our blog today. Zombies are all the fashion both in literature and on your computer. The question is: Are all zombies alike? Are there good and bad zombies, or only bad ones? How can you distinguish between good and evil intentions if all you got is a compromised system? It all boils down to trust, and the zombie in question is (again) the German Federal Trojan („Staatstrojaner“). The German magazine Telepolis published an article that compares the statement of Jörg Ziercke, the head of the German Federal Criminal Police Office (Bundeskriminalamt or BKA), to the words of Rudyard Kipling’s python Kaa. The basis for this analogue are Mr. Ziercke’s claims stem from leaked notes of his speech in the commission of the German

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Talks held at the Linuxwochen Wien

René Pfeiffer/ May 8, 2011/ Security, Veranstaltung

MiKa and me held three talks at the Linuxwochen Wien 2011. The scheduled talks were „VoIP Security“ and „The Wind Chill Factor of Security“. The third talk was a review of the trust models used with X.509 certificates and issued by certificate authorities. The review was a drop-in replacement talk for a speaker who did not show up. Since the talks were held in German, I’d like to present a short summary in our blog. VoIP has become a well-established technology in companies during the past years. Periodically we assess the security of VoIP protocols and implementations. The talk we gave was a review of the state-of-the-art focussing on SIP signalling and audio/video codecs. We discussed the basics, the SIP Digest Authentication Leak found by Sandro Gauci, SIP probes, the troubles of SIP gateway

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