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Top 10 Malware February 2018

The MS-ISAC observed a 19% decrease in new malware infections from January to February 2018. Kovter activity increased in February, accounting for 59% of the Top 10 Malware notifications. Every month the MS-ISAC maps the Top 10 Malware observed from monitoring state and local networks to common infection vectors. This is done by using open source observations and reports on each malware type. The malspam vector continues to remain the primary entry vector, increasing by 10% in February 2018, mostly due to the high levels of Kovter activity. Malspam is the only initiation vector that experienced an increase in February. Emotet activity continues its decline, decreasing from 11% of total activity in January, to 8% in February. Since remerging in January, the MS-ISAC continues to identify WannaCry activity on SLTT government networks. WannaCry stands as the second most prevalent malware. The malvertising vector continued a steady decline that began in October 2017.



February 2018 Malware1


February 2018 Malware Vector1


The MS-ISAC Top 10 Malware refers to the top 10 new actionable event notifications of non-generic malware signatures sent out by the MS-ISAC Security Operations Center (SOC).

Dropped – Malware dropped by other malware already on the system or by an exploit kit.

Malvertising – Malware introduced through a malicious advertisement.

Multiple – Refers to malware that currently favors at least two vectors.

Malspam – Unsolicited emails, which either direct users to download malware from malicious websites or trick the user into opening malware through an attachment.

  1. Kovter is a trojan, that has been observed acting as click fraud malware or a ransomware downloader. It is disseminated via malspam email attachments containing malicious Microsoft Office macros. Kovter is fileless malware that evades detection by hiding in registry keys. Some reports indicate that Kovter infections have received updated instructions from the command and control infrastructure to serve as a remote access backdoor.
  2. WannaCry is a ransomware cryptoworm that uses the EternalBlue exploit to spread. Version 1.0 has a “killswitch” domain, which stops the encryption process. WannaCry is disseminated via malspam.
  3. Emotet is a modular trojan that downloads or drops banking trojans. Initial infection occurs via malspam emails that contain either malicious download links or attachments, such as PDF or macro-enabled Word documents. Emotet also incorporates spreader modules in order to propagate throughout a network. Currently, there are four known spreader modules: Outlook scraper, WebBrowserPassView, Mail PassView, and a credential enumerator. Emotet is known to download/drop the Pinkslipbot and Dridex banking trojans.
  4. ZeuS is a modular banking trojan which uses keystroke logging to compromise victim credentials when the user visits a banking website. Since the release of the ZeuS source code in 2011, many other malware variants have adopted parts of it’s codebase, which means that events classified as ZeuS may actually be other malware using parts of the ZeuS code.
  5. NanoCore is a Remote Access Trojan (RAT) spread via malspam as a malicious Excel XLS spreadsheet. As a RAT, NanoCore can accept commands to download and execute files, visit websites, and add registry keys for persistence.
  6. CoinMiner is a cryptocurrency miner that is initially disseminated via malvertising. Once a machine is infected, CoinMiner uses Windows Management Instrumentation (WMI) and EternalBlue to spread across a network. CoinMiner uses the WMI Standard Event Consumer scripting to execute scripts for persistence.
  7. Gh0st is a RAT used to control infected endpoints. Gh0st is dropped by other malware to create a backdoor into a device that allows an attacker to fully control the infected device.
  8. Qarallex, or Qarallax, is a RATbased off an open source software called “LaZange.” It is capable of recording mouse movements and keyboard strokes, capturing webcam and screen activity, and performing credential scraping. Qarallex uses a JAVA file and runs on systems by using JAVA runtime environment (JRE).
  9. Latentbot malware is a modular trojan first identified in 2013. The trojan is known to be distributed by the RIG exploit kit. Latentbot primarily operates as a botnet, but it can create additional capabilities depending on the modules it downloads. These capabilities include keylogging, cookie stealing, and granting remote access.
  10. Mirai is a malware botnet known to compromise Internet of Things (IoT) devices in order to conduct large-scale distributed denial of service (DDoS) attacks. Mirai is dropped after an exploit has allowed the attacker to gain access to a machine.