InQuest Blog

Threat-hunting, malware, ransomware, vulnerability analysis and news from authors of InQuest.

Field Notes: Malicious HFS Instances Serving Gh0stRAT

Posted on 2018-07-09 by Adam Swanda

HTTP File Server, commonly abbreviated as HFS, is a free and simple means to send and receive files across the Internet. This also makes the software a popular choice among malicious actors for hosting and distributing malware and exploits, and an interesting target for malware researchers. An investigation into an HFS instance hosting an exploit for CVE-2018-8174 led to the discovery of an interesting threat actor and their infrastructure, the continued use of the Gh0st RAT malware, and many common attributes we can use to help us identify this malicious activity in the wild.

Plyara: Parsing YARA rules with Python

Posted on 2018-07-06 by Ryan Shipp

Plyara is a Python lexer and parser for YARA rules. You can use it to build your own tools around YARA rules: whether analyzing or performing bulk operations on a large corpus, parsing rule content for display, writing a linter, or any other application you might think of.

FormBook stealer: Data theft made easy

Posted on 2018-06-22 by Adam Swanda

The FormBook information stealing malware, being advertised as providing an "extensive and powerful internet monitoring experience", has clearly caught the eye of threat actors since its debut on underground forums in 2016. Due to its low price, it is easily available to a variety of actors and has therefore been distributed with varying methods of complexity and shows no signs of slowing down. The malware provides a variety of data theft capabilities such as stealing stored passwords from local applications, recording user keystrokes, browsing and interacting with files on the infected host, taking screenshots, and more. Although the information stealing functionality seems rather standard, the measures FormBook takes to avoid analysis makes this malware family difficult to detect and analyze, making the stealer all the more appealing to malicious actors looking for a new take on an old threat.

Phorpiex malware spreads GandCrab phishing emails

Posted on 2018-05-29 by Adam Swanda

Introduction

After analyzing the on-going GandCrab email distribution campaign, we at InQuest Labs decided to look further into the emails themselves and exactly how this malware is being propagated. Taking a second look at one of the payloads from our last analysis we found that the Phorpiex malware family acts as an email spreader for sending phishing emails with attachments. Immediately this jumped out at us as the culprit that is very likely the malware causing so much havoc across Internet mailboxes these past weeks.

By taking a closer look at the malware named in a previous blog post as "Trik" or Trik.pdb", we have now identified this as the malware family Phorpiex. Due to the families email spreader capability and unique strings found in the malware, it is highly likely to be responsible for the distribution of the GandCrab phishing campaigns we've seen in-the-wild over the past several weeks to months.

Field Notes: Agent Tesla Open Directory

Posted on 2018-05-22 by Adam Swanda

InQuest discovered an open directory hosting several Agent Tesla payloads, as well as several separate web panels for the administration of different Agent Tesla malware campaigns. We decided this was a good time to have a quick look at this malware family, it's capabilities, and the artifacts found in the open directory.

Agent Tesla is a malware family written in .NET for Microsoft Windows systems and has much in common with spyware in it's capabilities. It has many spyware like capabilities such as stealing credentials, keylogging, collecting screenshots, capturing web camera images, and gathering clipboard data, but it is often seen in more standard malware campaigns and uses common malware techniques for obfuscation, unpacking, and data collection. Recently, Agent Tesla has been distributed in the wild through phishing emails and malicious Word documents containing macros to drop and execute the malware.