Monday, July 24, 2017

Vulnerability Spotlight: FreeRDP Multiple Vulnerabilities

Vulnerabilities discovered by Tyler Bohan of Talos

Overview


Talos has discovered multiple vulnerabilities in the FreeRDP product. FreeRDP is a free implementation of the Remote Desktop Protocol (RDP) originally developed by Microsoft. RDP allows users to connect remotely to systems so they can be operated from afar. The open source nature of the FreeRDP library means that it is integrated into many commercial remote desktop protocol applications.

We identified a number of vulnerabilities falling into 2 classes:
  • 2 Code Executions;
  • 4 Denials Of Service.
The first category allows code execution on the client side through a specially crafted response from a RDP server. The second category can cause the termination of the FreeRDP client. The vulnerabilities result from weaknesses in the handling of network packets sent from the RDP server. Indeed, the size of the data needed to be parsed is sent from the server without checks on the client side. An attacker can compromise the server or use a man in the middle attack to trigger these vulnerabilities.

Friday, July 21, 2017

Threat Round-up for July 14 - July 21

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between July 14 and July 21. As with previous round-ups, this post isn't meant to be an in-depth analysis. Instead, this post will summarize the threats we've observed by highlighting key behavior characteristics, indicators of compromise, and how our customers are automatically protected from these threats.

As a reminder, the information provided for the following threats in this post is non-exhaustive and current as of date of publication. Detection and coverage for the following threats is subject to updates pending additional threat or vulnerability analysis. For the most current information, please refer to your Firepower Management Center, Snort.org, or ClamAV.net.

Thursday, July 20, 2017

Vulnerability Spotlight: Multiple Vulnerabilities in CorelDRAW X8


Today, Talos is disclosing several vulnerabilities that have been identified in CorelDRAW X8. CorelDRAW X8 is graphics suite used for manipulating raster and vector images and is a common alternative to Adobe Creative Cloud. Several of the vulnerabilities being disclosed today specifically affect PHOTO-PAINT X8, a raster graphics editor. Talos has responsibly disclosed this vulnerability to Corel. Corel has made a software update that addresses this vulnerability available for download.

Wednesday, July 19, 2017

Vulnerabilities in ProcessMaker, WebFOCUS, and OpenFire Identified and Patched

Today, Talos is disclosing several vulnerabilities that have been identified by Portcullis in various software products. All four vulnerabilities have been responsibly disclosed to each respective developer in order ensure they are addressed. In order better protect our customers, Talos has also developed Snort rules that detect attempts to exploit these vulnerabilities.

Vulnerability Details

TALOS-2017-0313 (CVE-2016-9048) ProcessMaker Enterprise Core Multiple SQL Injection Vulnerabilities

TALOS-2017-0313 was identified by Jerzy Kramarz of Portcullis.

TALOS-2017-0313 encompasses multiple SQL injection vulnerabilities in ProcessMarker Enterprise Core 3.0.1.7-community. These vulnerabilities manifest as a result of improperly sanitizing input received in web requests. An attacker who transmits a specifically crafted web request to an affected server with parameters containing SQL injection attacks could trigger this vulnerability. This could allow exfiltration of the database information, user credentials, and in certain configuration access the underlying operating system.

Unravelling .NET with the Help of WinDBG

This blog was authored by Paul Rascagneres and Warren Mercer.

Introduction


.NET is an increasingly important component of the Microsoft ecosystem providing a shared framework for interoperability between different languages and hardware platforms. Many Microsoft tools, such as PowerShell, and other administrative functions rely on the .NET platform for their functionality. Obviously, this makes .NET an enticing language for malware developers too. Hence, malware researchers must also be familiar with the language and have the necessary skills to analyse malicious software that runs on the platform.

Analysis tools such as ILSpy help researchers decompile code from applications, but cannot be used to automate the analysis of many samples. In this article we will examine how to use WinDBG to analyse .NET applications using the SOS extension provided by Microsoft.

This article describes:
  • How to analyse PowerShell scripts by inserting a breakpoint in the .NET API.
  • How to easily create a script to automatically unpack .NET samples following analysis of the packer logic.

Additionally, you can download a Python script (based on the WinDBG pykd extension) on our github to automate analysis of .NET. This script will be described in the article too.

Monday, July 17, 2017

PyREBox, a Python Scriptable Reverse Engineering Sandbox

This post was authored by Xabier Ugarte Pedrero


In Talos, we are continuously trying to improve our research and threat intelligence capabilities. As a consequence, we not only leverage standard tools for analysis, but we also focus our efforts on innovation, developing our own technology to overcome new challenges. Also, Talos has traditionally supported open-source projects, and has open-sourced many different projects and tools that are currently used as part of our workflow like FIRST and BASS

In this blogpost we present PyREBox, our Python scriptable Reverse Engineering sandbox. PyREBox is based on QEMU, and its goal is to aid reverse engineering by providing dynamic analysis and debugging capabilities from a different perspective. PyREBox allows to inspect a running QEMU VM, modify its memory or registers, and to instrument its execution with simple Python scripts. QEMU (when working as a whole-system-emulator) emulates a complete system (CPU, memory, devices...). By using Virtual Machine Introspection (VMI) techniques, it does not require to perform any modification into the guest operating system, as it transparently retrieves information from its memory at run-time.

Several academic projects such as DECAF, PANDA, S2E, or AVATAR, have previously leveraged QEMU based instrumentation for reverse engineering tasks. These projects allow to write plugins in C/C++, and implement several advanced features such as dynamic taint analysis, symbolic execution, or even record and replay of execution traces. With PyREBox, we aim to apply this technology focusing on keeping the design simple, and on the usability of the system for threat analysts.

Memcached - A Story of Failed Patching & Vulnerable Servers

This blog authored by Aleksandar Nikolich and David Maynor with contributions from Nick Biasini

Memcached - Not secure, Not Patched Fast Enough

 

Recently high profile vulnerabilities in systems were used to unleash several global ransomware attacks that greatly impacted organizations. These types of vulnerabilities were previously patched and could have been addressed by organizations before the attacks commenced. This is just the latest example in a long line of threats that are successful in large part because of the inability for patches to be applied in a timely and effective manner. In late 2016 Talos disclosed a series of vulnerabilities in a software platform called Memcached. After releasing the vulnerabilities Talos has been monitoring the amount of systems that were vulnerable as well as the rate at which they have been patched. This blog will give a quick overview of the vulnerabilities and discuss the unfortunate findings of the Internet wide scans that we have been conducting over the last six months.

Tuesday, July 11, 2017

Microsoft Patch Tuesday - July 2017

Today, Microsoft has release their monthly set of security updates designed to address vulnerabilities. This month's release addresses 54 vulnerabilities with 19 of them rated critical, 32 rated important, and 3 rated moderate. Impacted products include Edge, .NET Framework,  Internet Explorer, Office,  and Windows.

Vulnerability Spotlight: Iceni Infix PDF Editor Memory Corruption

Today, Talos is disclosing a vulnerability that has been identified in Iceni Infix PDF Editor that could lead to arbitrary code execution on affected hosts. This vulnerability manifests in a way that could be exploited if a user opens a specifically crafted PDF file that triggers this flaw. Talos has coordinated with Iceni to ensure relevant details regarding the vulnerability have been shared. Iceni has developed a software update that addresses this vulnerability. In addition, Talos has developed Snort Rules that can detect attempts to exploit this flaw.

Friday, July 7, 2017

Attack on Critical Infrastructure Leverages Template Injection


Contributors:  Sean Baird, Earl Carter, Erick Galinkin, Christopher Marczewski & Joe Marshall 


Executive Summary


Attackers are continually trying to find new ways to target users with malware sent via email. Talos has identified an email-based attack targeting the energy sector, including nuclear power, that puts a new spin on the classic word document attachment phish. Typically, malicious Word documents that are sent as attachments to phishing emails will themselves contain a script or macro that executes malicious code. In this case, there is no malicious code in the attachment itself. The attachment instead tries to download a template file over an SMB connection so that the user's credentials can be silently harvested. In addition, this template file could also potentially be used to download other malicious payloads to the victim's computer.