Misc

Security Advisory for VMware vRealize Automation Center

During a recent customer project we identified several vulnerabilities in the VMware vRealize Automation Center such as a DOM-based cross-site scripting and a missing renewal of session tokens during the login. The vulnerabilities have been disclosed to VMware on November 20th, 2017. A security advisory for the vulnerabilities has been made available here on April 12th, 2018.

Just a few words regarding the cross-site scripting vulnerability. This vulnerability is present within a GET request to the URL /vcac/gadgets/ifr because of certain URL parameters whose values are directly passed to an eval function call. The vulnerable parameters are gwt:onLoadErrorFn and gwt:onPropertyErrorFn. It seems that these parameters are actually never used by the application and we only found them by looking at the source code.

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Misc

Creating Static Binaries for Nmap, Socat and other Tools

In various scenarios it might be helpful or even required to have a statically compiled version of Nmap available. This applies to e.g. scenarios where only limited user privileges are available and installing anything to the system might not be desirable.

For such cases I’ve started to create recipes to build such binaries. Similar projects are already available on GitHub, but there are several reasons why I chose to create my own tools:

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Misc

White Paper on Incident Analysis and Forensics in Docker Environments

In this article, we describe the impact of the increased use of Docker in corporate environments on forensic investigations and incident analysis. Even though Docker is being used more and more (Portworx, Inc., 2017), the implications of the changed runtime environment for forensic processes and tools have barely been considered. We describe the technological basics of Docker and, based on them, outline the differences that occur with respect to digital evidence and previously used methods for evidence acquisition. Specifically, we look at digital evidence within a Docker container which are lost or need to be acquired in different ways compared to a classical virtual machine, and what new traces and opportunities arise from Docker itself.

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Misc

White Paper on Multi-Factor Authentication in Microsoft Windows Environments

A new ERNW whitepaper was just published. I wrote this whitepaper in the course of my bachelor thesis and it examines multi-factor authentication in Microsoft Windows environments:

Credential theft and the subsequent reuse of stolen credentials are a significant problem in today’s information security. To counter the associated risks, a planned approach is required as part of a comprehensive security architecture program. This includes the implementation of multi-factor authentication as an important building block. This whitepaper covers the relevant steps of implementing a multi-factor authentication system in an enterprise environment and closes with a security evaluation.

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Misc

Interacting with the BlueCoat Filesystem

the last post was about a fuse filesystem which provides a read-only access to the proprietary bluecoat filesystem. After some further investigations based on the possibilities this offered us, I started to implement a tool which allows to modify parts of the filesystem.

Protection Mechanisms

Since last time, the discovered filesystem structures still had unknown fields. Some of those fields could be reconstructed and their purpose in the whole construct. The format of the Partition-Header for example could now be described as

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Misc

An Update of PenTesting Tools that (do not) Support IPv6

As you may remember, back in 2014 we published a whitepaper (compiled by Antonis Atlasis) on the support of IPv6 in different pentesting tools. This is almost three years ago and we thought it is time for an update. In short not much has changed. Most of the tools which didn’t support IPv6 are still not supporting it or haven’t got any update since then.
This post will  cover the tools where we could identify some progress on supporting IPv6.

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Misc

Local Packet Filtering with IPv6

Just recently we discussed IPv6 filter rules for NIC-level firewalls (in a virtualized data center) with a customer. I’d like to take this as an opportunity to lay out potential approaches for local packet filtering of IPv6, which in turn might somewhat depend on the address configuration strategy chosen for the respective systems (for the latter you may refer to this post or to this talk from the Troopers NGI event).

Some of this has already been discussed in RFC 4890 Recommendations for Filtering ICMPv6 Messages in Firewalls but that document is from 2007 and things may have changed in the interim.
Let’s start with a quick look at the traffic which might be of interest. We will take a server perspective here, read: which types of IPv6 traffic might have to be accepted by a host/NIC firewall in order to support proper operations? I will discuss the following, with a focus on the implications of filtering them locally:

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Misc

Testing RFC 6980 Implementations of FreeBSD

Following Enno’s research on “Testing RFC 6980 Implementations with Chiron“, we decided to redo the experiment with FreeBSD targets.

The lab setup was very similar:

  • A Cisco Catalyst 3560 switch running the software “C3560c405ex-UNIVERSALK9-M” version 15.2(2)E4 connecting
  • A Linux based attacker system running Chiron and
  • A FreeBSD target system, running different OS versions and configurations and
  • A Linux based laptop running a control script that remotely performed the necessary tasks on the two machines mentioned above

The main question was: Would the impact on the target system and the possible attacks that were observed with the Windows Server 2016 victim be reproducible on other operating systems? Or would those behave totally differently?

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Misc

GDPR and Pseudonymisation – Easing the Pain of Regulation

27 April 2016 marked a turning point for a lot of countries as well as a lot businesses worldwide: EU regulation 2016/679 (going by it’s more widely known name General Data Protection Regulation and abbreviated GDPR) was adopted by the European Parliament, the Council as well as the Commission [1]. Especially readers from countries outside of the EU might ask “Why should this be of interest for me?”.

The point is: if your business is dealing with data of EU citizens (e.g. because you are having an online shop selling goods in the EU, or you operate a social network platform with customers that are EU citizens) you are liable under GDPR – this is regulated in Article 3, section 2 of the regulation: “This Regulation applies to the processing of personal data of data subjects residing in the Union by a controller not established in the Union, where the processing activities are related to:
(a) the offering of goods or services to such data subjects in the Union; or
(b) the monitoring of their behaviour.”
I’d guess that if you are reading these lines you become aware (if not have been so before) that your business might most probably be affected by GDPR as well. Now, the purpose of this blog post is not to enlighten you on the basics of GDPR but to discuss one special, interesting aspect of this regulation: pseudonymisation and how it might support your way to become compliant with GDPR.

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