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  • COINHOARDER: Tracking a Ukrainian Bitcoin Phishing Ring DNS Style

    - February 14, 2018 - 0 Comments

    This post is authored by Jeremiah O’Connor and Dave Maynor with contributions from Artsiom Holub and Austin McBride. 

    Executive Summary

    Cisco has been tracking a bitcoin theft campaign for over 6 months. The campaign was discovered internally and researched with the aid of an intelligence sharing partnership with Ukraine Cyberpolice. The campaign was very simple and after initial setup the attackers needed only to continue purchasing Google AdWords to ensure a steady stream of victims. This campaign targeted specific geographic regions and allowed the attackers to amass millions in revenue through the theft of cryptocurrency from victims. This campaign demonstrates just how lucrative these sorts of malicious attacks can be for cybercriminals. Additionally, the revenue generated by these sorts of attacks, can then be reinvested into other cybercriminal operations.


  • Microsoft Patch Tuesday – February 2018

    - February 13, 2018 - 0 Comments

    Microsoft Patch Tuesday – February 2018

    Today Microsoft has released its monthly set of security advisories for vulnerabilities that have been identified and addressed in various products. This month’s advisory release addresses 54 new vulnerabilities with 14 of them rated critical, 38 of them rated important, and 2 of them rated Moderate. These vulnerabilities impact Outlook, Edge, Scripting Engine, App Container, Windows, and more.

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  • Olympic Destroyer Takes Aim At Winter Olympics

    - February 12, 2018 - 0 Comments

    The Winter Olympics this year is being held in Pyeongchang, South Korea. The Guardian, a UK Newspaper reported an article that suggested the Olympic computer systems suffered technical issues during the opening ceremony. Officials at the games confirmed some technical issues to non-critical systems and they completed recovery within around 12 hours. Sunday 11th February the Olympic games officials confirmed a cyber attack occurred but did not comment or speculate further.

    Talos have identified the samples, with moderate confidence, used in this attack. The infection vector is currently unknown as we continue to investigate. The samples identified, however, are not from adversaries looking for information from the games but instead they are aimed to disrupt the games. The samples analysed appear to perform only destructive functionality. There does not appear to be any exfiltration of data. Analysis shows that actors are again favouring legitimate pieces of software as PsExec functionality is identified within the sample. The destructive nature of this malware aims to render the machine unusable by deleting shadow copies, event logs and trying to use PsExec & WMI to further move through the environment. This is something we have witnessed previously with BadRabbit and Nyetya.


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  • Targeted Attacks In The Middle East

    - February 6, 2018 - 0 Comments

    This blog post is authored by Paul Rascagneres with assistance of Martin Lee.

    Executive Summary

    Talos has identified a targeted attack affecting the Middle East. This campaign contains the following elements, which are described in detail in this article.

    • The use of allegedly confidential decoy documents purported to be written by the Jordanian publishing and research house, Dar El-Jaleel. This institute is known for their research of the Palestinian-Israeli conflict and the Sunni-Shia conflict within Iran.
    • The attacker extensively used scripting languages (VBScript, PowerShell, VBA) as part of their attack. These scripts are used to dynamically load and execute VBScript functions retrieved from a Command & Control server.
    • The attacker demonstrates excellent operational security (OPSEC). The attacker was particularly careful to camouflage their infrastructure. During our investigation, the attacker deployed several reconnaissance scripts in order to check the validity of victim machine, blocking systems that don’t meet their criteria. The attacker uses the reputable CloudFlare system to hide the nature and location of their infrastructure. Additionally, the attacker filters connections based on their User-Agent strings, and only enables their infrastructure for short periods of time before blocking all connections.


  • Flash 0-Day In The Wild: Group 123 At The Controls

    - February 2, 2018 - 0 Comments

    The 1st of February, Adobe published an advisory concerning a Flash vulnerability (CVE-2018-4878). This vulnerability is a use after free that allows Remote Code Execute through a malformed Flash object. Additionally KISA (Korean CERT) published an advisory about a Flash 0-day used in the wild. Talos identified that an attacker exploited this vulnerability with a Flash object embedded in a Microsoft Excel document. By opening the document, the exploit was executed in order to download an additional payload from a compromised website.


  • Ransom Where? Malicious Cryptocurrency Miners Takeover, Generating Millions

    - January 31, 2018 - 0 Comments

    The Dark Side of the Digital Gold Rush

    This post was authored by Nick BiasiniEdmund BrumaghinWarren Mercer and Josh Reynolds with contributions from Azim Khodijbaev and David Liebenberg.

    Executive Summary

    The threat landscape is constantly changing; over the last few years malware threat vectors, methods and payloads have rapidly evolved. Recently, as cryptocurrency values have exploded, mining related attacks have emerged as a primary interest for many attackers who are beginning to recognize that they can realize all of the financial upside of previous attacks, like ransomware, without needing to actually engage the victim and without the extraneous law enforcement attention that comes with ransomware attacks.

    This focus on mining isn’t entirely surprising, considering that various cryptocurrencies along with “blockchain” have been all over the news as the value of these currencies has exponentially increased. Adversaries have taken note of these gains and have been creating new attacks that help them monetize this growth. Over the past several months Talos has observed a marked increase in the volume of cryptocurrency mining software being maliciously delivered to victims.

    In this new business model, attackers are no longer penalizing victims for opening an attachment, or running a malicious script by taking systems hostage and demanding a ransom. Now attackers are actively leveraging the resources of infected systems for cryptocurrency mining. In these cases the better the performance and computing power of the targeted system, the better for the attacker from a revenue generation perspective. IoT devices, with their lack of monitoring and lack of day to day user engagement, are fast becoming an attractive target for these attackers, as they offer processing power without direct victim oversight. While the computing resources within most IoT devices are generally limited, the number of exposed devices that are vulnerable to publicly available exploits is high which may make them attractive to cyber criminals moving forward.

    To put the financial gains in perspective, an average system would likely generate about $0.25 of Monero per day, meaning that an adversary who has enlisted 2,000 victims (not a hard feat), could generate $500 per day or $182,500 per year. Talos has observed botnets consisting of millions of infected systems, which using our previous logic means that these systems could be leveraged to generate more than $100 million per year theoretically. It is important to note that due to volatility present across cryptocurrency markets, these values may change drastically from day to day. All calculations in this blog were made based on XMR/USD at the time of this writing.


  • 2017 in Snort Signatures.

    - January 29, 2018 - 0 Comments

    2017 was an eventful year for cyber security with high profile vulnerabilities that allowed self-replicating worm attacks such as WannaCry and BadRabbit to impact organizations throughout the world. In 2017, Talos researchers discovered many new attacks including backdoors in legitimate software such as CCleaner, designed to target high tech companies as well as M.E.Doc, responsible for initial spread of Nyetya. Despite all those, headline making attacks are only a small part of the day to day protection provided by security systems.

    In this post we review some of the findings created by investigating the most frequently triggered Snort signatures as reported by Cisco Meraki systems and included in the Snort default policy set.


  • Vulnerability Spotlight: Walt Disney Per-Face Texture Mapping faceInfoSize Code Execution Vulnerability

    - January 26, 2018 - 0 Comments

    This vulnerability was discovered by Tyler Bohan of Cisco Talos.

    Executive Summary

    Walt Disney PTEX is an open source software application maintained by Walt Disney Animation Studios. It is designed for use in post-production rendering. It allows for the storage of thousands of texture mappings within a single file. This particular software library is in many other software applications such as Pixar’s RenderMan, giving it a large install base. A list of other applications that have incorporated PTEX is available here. Talos has recently discovered a stack-based buffer overflow in PTEX that could potentially allow a remote attacker to execute arbitrary code on affected systems.


  • SamSam – The Evolution Continues Netting Over $325,000 in 4 Weeks

    - January 22, 2018 - 1 Comment
    Talos have been working in conjunction with Cisco IR Services on what we believe to be a new variant of the SamSam ransomware. This ransomware has been observed across multiple industries including Government, Healthcare and ICS. These attacks do not appear to be highly targeted, and appear to be more opportunistic in nature.
    Given SamSam’s victimology its impacts are not just felt within the business world, they are also impacting people, especially if we consider the Healthcare sector. Non urgent surgeries can always be rescheduled but if we take as an example patients where the medical history and former medical treatment are crucial the impact may be more severe. Furthermore, many critical life savings medical devices are now highly computerized. Ransomware can impact the operation of these devices making it very difficult for medical personnel to diagnose and treat patients leading to potentially life threatening situations. Equipment that might be needed in time-sensitive operations may be made unavailable due to the computer used to operate the equipment being unavailable.
    The initial infection vector for these ongoing attacks is currently unknown and Talos is investigating this in order to identify it. The history of SamSam indicates that attackers may follow their previous modus operandi of exploiting a host and then laterally moving within their target environment to plant and later run the SamSam ransomware. Previously, we observed the adversaries attacking vulnerable JBoss hosts during a previous wave of SamSam attacks in 2016. Although the infection vector for the new variant is not yet confirmed, there is a possibility that compromised RDP/VNC servers have played a part in allowing the attackers to obtain an initial foothold.
  • The Many Tentacles of the Necurs Botnet

    - January 18, 2018 - 1 Comment

    This post was written by Jaeson Schultz.


    Over the past five years the Necurs botnet has established itself as the largest purveyor of spam worldwide. Necurs is responsible for emailing massive amounts of banking malware, ransomware, dating spam, pump-n-dump stock scams, work from home schemes, and even cryptocurrency wallet credential phishing. Necurs sends so much spam that at times Necurs’ spam campaigns can make up more than 90% of the spam seen by Cisco Talos in one day.

    To conduct a deeper analysis of Necurs, Talos extracted 32 distinct spam campaigns sent by Necurs between August 2017 and November 2017. The result was a collection of over 2.1 million spam messages, sent from almost 1.2 million distinct sending IP addresses in over 200 countries and territories.

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