While doing heap research on Linux processes (results are going to be published soon), I came across the bot from the Mirai Botnet. As already mentioned in the blog post by Brian, the Mirai bot uses obfuscated configuration data which contains e.g. the CnC server. When now confronted only with a bot (e.g. in the context of a running task or the ELF binary), but without the according source code, the decryption of this configuration data for e.g. incident analysis purposes might not be easily possible (with the python script from the blog post), if the key has been changed.
But in this case that is not a problem at all, because
Malware
Teaser on the TROOPERS16 Incident Analysis Workshop: Analyzing the current Spam Flood
As we are giving another round of our Incident Analysis workshop at Troopers16, we wanted to give a little sample taste what you can expect.
Table of Contents
Extracting Mail Attachments
Word Document Analysis
Static JavaScript Analysis
Dynamic JavaScript Analysis
Before we dive into the analysis, I wanted to mention that if you are going to analyze anything unknown/potentially malicious, do it in a safe environment (VM with no internet connection, in the best case on a separate physical analysis device, or at least strip all unnecessary functionality from that VM (CVE-2015-3456 is an example to answer the “why”)). Even things like looking at content with a text editor or extracting zip files should be done in the safe environment, as those tools could contain vulnerabilities.
Continue readingInvestigating Memory Analysis Tools – SSDT Hooking via Pointer Replacement
In this blogpost we will briefly explain a well known Syscall hooking technique (a more detailed explanation can be gathered from e.g. http://resources.infosecinstitute.com/hooking-system-service-dispatch-table-ssdt/) used by multiple malware samples (like the laqma trojan) and right after discuss how some memory analysis tools have trouble in the analysis and/or reporting of these.
Before we go further, I just shortly wanted to say, that this post is not intended to be a bashing of any tool. We have the greatest respect for all the effort and work which has been and most probably will be done in the future.
Continue readingBeing at VB2015…
I am currently at the 25th Virus Bulletin International Conference in Prague. The VB2015 is hosted by the Virus Bulletin portal and provides three full days of learning opportunities and networking.
VB2015 focuses on the key themes:
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Malware & botnets
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Anti-malware tools & techniques
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Mobile devices
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Hacking & vulnerabilities
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Spam & social networks
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Network security
General Observations:
What I liked about VB2015 was the very friendly and always helpful staff. The good conference location, it never felt overcrowded or to empty and the very good catering during the conference.
Continue readingEvaluating Behavior-based Malware Detection
Quite some organizations complemented their traditional AV solutions with a technology that can best be described as behavior-based malware detection. While we all know we are talking about products like Fireeye Email/Network Security, zScaler Web Security/APT Protection, or Cisco WSA, there are a lot of terms around to describe this type of products (such as next generation malware analysis/detection, Secure Web Gateways, or behavior-based malware detection). Those offerings typically promise the detection of malware by analyzing the behavior of ‘samples’ (which are files captured in transit of different types, such as executables or PDF documents). However, beyond the taxonomy challenges, both assessment and consulting work gets us frequently in contact with those solutions. While the main task during assessments is to bypass those solutions, the main question in the consulting context typically is “to what degree are the solutions suited to protect from common targeted attacks in the enterprise context”. Luckily, the experience from assessment work allows us to tackle this question in a structured way (which is our approach for consulting anyways: Benefit from our assessment experiences in order to provide reasonable consulting advice…).
Continue readingSkeleton Key – a Nasty Piece of Malware. Some Remarks.
Just recently, Dell SecureWorks Counter Threat Unit(TM) (CTU) researchers published details (see http://www.secureworks.com/cyber-threat-intelligence/threats/skeleton-key-malware-analysis/ ) on a especially nasty piece of malware that bypasses authentication on Active Directory (AD) systems which implement single-factor (password only) authentication. Once deployed the malware stays quite noiseless in the Domain Controller´s (DC) RAM, and the DC´s replication issues caused by it weren´t interpreted – in this case – during months as a hint for system compromise. Probably the malware´s modification on the LSASS process reduced the DC´s ability to perform DC-to-DC authentication, but this is only speculation and not where we would like to go today.
Continue readingAppstore security: 5 lines of defence against malware
A few days ago the European Network and Information Security Agency (ENISA) published this quite interesting document with the exact title. Here’s what it covers:
“The booming smartphone industry has a special way of delivering software to end-users: appstores. Popular appstores have hundreds of thousands of apps for anything from online banking to mosquito repellent, and the most popular stores (Apple Appstore, Google Android market) claim billions of app downloads. But appstores have not escaped the attention of cyber attackers. Over the course of 2011 numerous malicious apps were found, across a variety of smartphone models. Using malicious apps, attackers can easily tap into the vast amount of private data processed on smartphones such as confidential business emails, location data, phone calls, SMS messages and so on. Starting from a threat model for appstores, this paper identifies five lines of defence that must be in place to address malware in appstores: app review, reputation, kill-switches, device security and jails.”
Continue readingThat “new worm”…
Recently I noticed this news titled “New email worm on the move”. At roughly the same time I received an email from a senior security responsible from a large customer asking for mitigation advice as they got “hit pretty hard” (by this exact piece of malware).
Given I’m mainly an infrastructure and architecture guy usually I’m not too involved in malware protection stuff (besides my continuous ranting that – from an architectural point of view – endpoint based antivirus has a bad security benefit vs. capex/opex ratio). So I’m by no means an expert in this field. Still I keep scratching my head when I read the associated announcements (like this, this or this) from major “antivirus”, “malware protection” or “endpoint security” vendors – to save typing, in the remainder of the post I call them SNAKE vendors (where “SNAKE” stands for “Smart Nimble APT Kombat Execution”… or sth equally ingenious of the valued reader’s choice… 😉