How to crack the challenges of DIVA

DIVA is a vulnerable Android app that is a good start to teach students how to check for vulnerabilities or design flaws in Android apps. According to the developers, “DIVA (Damn insecure and vulnerable App) is an App intentionally designed to be insecure. The aim of the App is to teach developers/QA/security professionals, flaws that are generally present in the Apps due poor or insecure coding practices.”

Within this Blogpost, I want to help you cracking the 13 challenges of DIVA.

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Defeating the Secrets of OTP Apps for Android

Despite the increasing number of cases of data theft (such as Equifax), the classic password is still in many places the sole security feature for user authentication.

However, numerous possibilities for extending this now anachronistic form of access control already exist. One such option is the use of one-time passwords (OTP). These passwords are increasingly used for additional authentication (in addition to user name and password) of the respective user to service providers on the Internet and the applications that generate these are therefore referred to as so-called two-factor authentication apps (2FA apps).

The paper of Philip Polleit and myself investigates 16 such 2FA apps for the Android operating system and focuses on the extent to which these applications can offer a similar level of protection when compared to classical hardware tokens (e.g., YubiKey, SecurID-Authenticator). The paper was presented at this years IMF conference in Hamburg.

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Codeinspect: The all-in-one Platform for Android App Analysis

I’ve started some months ago with a post about Androguard and how to use it for reversing of Android apps. Androguard is still one of the most common tools for malware analysis and pentesting of Android apps, but there is a new tool on the horizon that I really want to show you. This tool combines a lot of the tasks that an analyst is facing during his day-to-day work routine in just one UI. The Tool is called Codeinspect and is developed at the Fraunhofer SIT.

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Overview: Cryptolocker and Ransomware

Within the past 2 years, in addition to the conventional malware, the so-called Ransomware has spread massively. While in 2014 less than 10 known families/variants roamed in this area, we discovered 15 of those blackmailing apps in 2015. Within the first quarter of 2016 this number has already been exceeded (as can be seen in the table below). Last year, we saw a special form of Ransomware appearing, the so-called Cryptolocker. This special form is feared by users and security responsible people within an organization because it blocks not only the smartphone or tablet – as it is the case with Ransomware – but also all data of the user becomes encrypted on an infected device.

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Our Android Malware Summary for the Year 2015

In 2015 our Mobile-Sandbox analyzed only 25,000 Android applications that were submitted by mostly anonymous users, Anti-Virus-Companies and by our own. In the same time we had a large outage of the system (more than 4 months) due to some hardware defects and missing free time to get the system running again (I still hope to get it available for the public by end of this month).

Most of these malicious applications had been downloaded from Third-Party markets and from potentially infected mobile devices. When looking at the malicious and unwanted applications and the corresponding families, one can see the following distribution of malicious behavior:

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