Friday, April 21, 2017

Vulnerability Spotlight: Hard-coded Credential Flaw in Moxa ICS Wireless Access Points Identified and Fixed

Earlier this month, Talos responsibly disclosed a set of vulnerabilities in Moxa ICS wireless access points. While most of the vulnerabilities were addressed in the previous set of advisories, Talos has continued to work with Moxa to ensure all remaining vulnerabilities that Talos identified are patched. Today in coordination with Moxa, Talos is disclosing the TALOS-2016-0231, a hard-coded credential vulnerability that could allow an attacker to gain complete control of the device. Moxa has released a software update to address TALOS-2016-0231 and other bugs.

Threat Spotlight: Mighty Morphin Malware Purveyors: Locky Returns Via Necurs

This post was authored by Nick Biasini

Throughout the majority of 2016, Locky was the dominant ransomware in the threat landscape. It was an early pioneer when it came to using scripting formats Windows hosts would natively handle, like .js, .wsf, and .hta. These scripting formats acted as a vehicle to deliver the payload via email campaigns. However, late in 2016 Locky distribution declined dramatically largely due to the slowdown of Necurs that occurred at the same time.

On April 21st, Talos observed the first large scale Locky campaign in months from Necurs. This campaign leveraged techniques associated with a recent Dridex campaign and is currently being distributed in very high volumes. Talos has seen in excess of 35K emails in the last several hours associated with this newest wave of Locky. This large wave of distribution has been attributed to the Necurs botnet which, until recently, had been focused on more traditional spam such as pump-and-dump spam, Russian dating spam, and work-from-home spam.

Threat Round-up for Apr 14 - Apr 21

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between April 14 and April 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 FireSIGHT Management Center, Snort.org, or ClamAV.net.

Wednesday, April 19, 2017

Vulnerability Spotlight: ARM Mbedtls x509 ECDSA invalid public key Code Execution Vulnerability

Vulnerability Discovered by Aleksandar Nikolic

Overview

Talos is disclosing TALOS-2017-0274/CVE-2017-2784, a code execution vulnerability in ARM MbedTLS. This vulnerability is specifically related to how MbedTLS handles x509 certificates. MbedTLS is an SSL/TLS implementation aimed specifically at embedded devices that was previously known as PolarSSL. 

The vulnerability exists in the part of the code responsible for handling elliptic curve cryptography keys. An attacker can trigger this vulnerability by providing a specially crafted x509 certificate to the target which performs a series of checks on the certificate. While performing these checks the application fails to properly parse the public key. This results in the invalid free of a stack pointer. There is a mitigating factor associated with this vulnerability in that the memory space that is pointed to is zeroed out shortly before the vulnerability is triggered. However, since it's designed to be used in embedded platforms that may not have modern heap exploitation mitigations in place it may be possible to achieve code execution in certain circumstances.  Full details of the vulnerability are available in our advisory.

Tuesday, April 18, 2017

Vulnerability Spotlight: Information Disclosure Vulnerability in Lexmark Perceptive Document Filters

Discovered by Marcin 'Icewall' Noga of Cisco Talos.

Talos are today releasing a new vulnerability discovered within the Lexmark Perceptive Document Filters library. TALOS-2017-0302 allows for information disclosure using specifically crafted files.

Overview


The vulnerability is present in the Lexmark Document filter parsing engine which is used across a wide range of services such as eDiscovery, DLP, big data, content management and others. The library is commonly used across these services to allow for the deep inspection of a multitude of file formats to offer conversion capabilities such as from Microsoft document formats into other formats. Lexmark make this library available to compete against other third party and open source libraries used for such activities.

Document conversion represents an important aspect of many businesses as they attempt to move from an unstructured data solution to a more workable structured data solution in order to improve business efficiency.

Saturday, April 15, 2017

Cisco Coverage for Shadow Brokers 2017-04-14 Information Release

On Friday, April 14, the actor group identifying itself as the Shadow Brokers released new information containing exploits for vulnerabilities that affect various versions of Microsoft Windows as well as applications such as Lotus Domino. Additionally, the release included previously unknown tools, including an exploitation framework identified as "FUZZBUNCH." Preliminary analysis of the information suggested several of the released exploits were targeting zero-day vulnerabilities. Microsoft has released a statement regarding the newly released exploits targeting Windows and notes that most of them have been previously patched. Talos is aware of this new information disclosure and has responded to ensure our customers are protected from these threats.

Coverage for the exploits and tools disclosed by the Shadow Brokers is available through Cisco's security products, services, and open source technologies. In some cases, coverage for specific tools or vulnerabilities was already available prior to today's information release. In the cases of the exploits dubbed ETERNALCHAMPION and ETERNALBLUE, Talos had pre-existing coverage that detects attempts to exploit these vulnerabilities.

Friday, April 14, 2017

Threat Round-up for Apr 7 - Apr 14

Today, Talos is publishing a glimpse into the most prevalent threats we've observed between April 7 and April 14. 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 FireSIGHT Management Center, Snort.org, or ClamAV.net.

Cisco Coverage for CVE-2017-0199

Over the past week, information regarding a serious zero-day vulnerability (CVE-2017-0199) in Microsoft Office was publically disclosed. Since learning of this flaw, Talos has been actively investigating the issue. Preliminary reports indicated that this vulnerability was actively being exploited in the wild and used to compromise hosts with Dridex, a well-known banking trojan.

On Tuesday, April 11, Microsoft released a patch for CVE-2017-0199. CVE-2017-0199 is an arbitrary code execution vulnerability in Microsoft Office which manifests due to improper handling of Rich Text Format (RTF) files. Exploitation of this flaw has been observed in email-based attacks where adversaries bait users to open a specifically crafted document attached to the message. Given that this vulnerability continues to be actively being exploited, Talos strongly recommends all customers patch as soon as possible.

Tuesday, April 11, 2017

Microsoft Patch Tuesday - April 2017

It’s that time again! Today we bring you April’s Microsoft Patch Tuesday information. These fixed vulnerabilities affect Outlook, Edge, Internet Explorer, Hyper-V, .NET, and Scripting Engine.


Monday, April 10, 2017

From Box to Backdoor: Discovering Just How Insecure an ICS Device is in Only 2 Weeks

This post was authored by Martin Lee and Warren Mercer, based on research conducted by Patrick DeSantis.

*blog post was updated with additional information for Day 4 on April 21. 

Industrial Control Systems provide stability to civilization. They clean our water, deliver our power, and enable the physical infrastructure that we have learnt to rely on. Industrial Control Systems are also highly prevalent in manufacturing. They're the robots who build your cars and assemble T.V's, they're the forklifts that ship your e-commerce purchases. As factories, utilities, and other industrial companies shift to a modern industrial infrastructure, it's vital that those processes and devices remain safe from attackers.

One key component in any ICS architecture is the access point which provides the connection between ICS devices and a industrial wireless network. Inspired by From LOW to PWNED we decided to take a look at one ICS wireless access point and see just how many vulnerabilities we could find in two weeks. The vulnerabilities listed in this post have been responsibly disclosed to Moxa. Moxa has released a software update that addresses most of these vulnerabilities. Additional updates will be forthcoming that will address TALOS-2017-0231.