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Top 10 Malware June 2019

The identified malware variants remain mostly consistent with the previous month, except for the return of WannaCry and Tinba activity. The proportion of Top 10 Malware to Total Malware activity remains above the 60% mark since April, indicating that the most prolific malware are driving the trends within malware activity. Top 10 Malware activity accounted for 63% of Total Malware notifications in June, a 3% increase from May.


In June 2019, malware utilizing multiple initiation vectors accounted for the greatest number of alerts in the Top 10 malware list. An increase in Trickbot infections accounts for the spike in activity within the multiple category. The significant decrease in the dropped vector is due to the decline of Qakbot activity. After February, the malvertisement vector returned to its previous levels of non-activity, as no malware using this vector made it into the Top 10 list. In May, the MS-ISAC disabled some duplicate and low confidence signatures associated with WannaCry resulting in a decrease in alerts. The activity is now returned at low levels in June.


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 delivered by other malware already on the system, an exploit kit, infected third-party software, or manually by a cyber threat actor. Currently, Gh0st and Pushdo are being dropped.

Multiple – Malware that currently favors at least two vectors. ZeuS, CoinMiner, and Trickbot are currently utilizing multiple vectors. ZeuS is dropped by other malware, but it is also delivered via malvertisement. CoinMiner utilizes the malspam and dropped vectors. Trickbot is dropped by Emotet and also delivered via malspam.

Malspam – Unsolicited emails, which either direct users to malicious web sites or trick users into downloading or opening malware. Top 10 Malware using this technique include NanoCore, Kovter, Dridex, and Tinba.

Network – Malware introduced through the abuse of legitimate network protocols or tools, such as SMB protocol or remote PowerShell.

Malvertisement – Malware introduced through malicious advertisements. Shlayer, a MacOS trojan, is the first malware since May 2018 to rely on this vector within the Top 10 Malware list.

  1. Trickbot is a modular banking trojan that is known to be dropped by Emotet as well as spread via malspam campaigns. Trickbot is also known to download the IcedID banking trojan.
  2. Dridex is a banking trojan that uses malicious macros in Microsoft Office with either malicious embedded links or attachments. Dridex is disseminated via malspam campaigns.
  3. WannaCry is a ransomware cryptoworm that uses the EternalBlue exploit to spread via SMB protocol. WannaCry has a “killswitch” domain, which stops the encryption process.
  4. 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.
  5. 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 June actually be other malware using parts of the ZeuS code.
  6. NanoCore is a 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.
  7. CoinMiner is a cryptocurrency miner that 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. CoinMiner spreads through malspam or is dropped by other malware.
  8. Kovter is a fileless click fraud malware and a downloader that evades detection by hiding in registry keys. Reporting indicates that Kovter can have backdoor capabilities and uses hooks within certain APIs for persistence.
  9. Pushdo is a botnet that has been active since 2007 and operates as a service for malware and spam distribution. Pushdo is known to distribute the Cutwail spambot. The malware uses encrypted communication channels and domain generation algorithms to send instructions to its zombie hosts.
  10. Tinba (aka Tiny Banker) is a banking trojan, known for its small file size. Tinba uses web injection to collect victim information from login pages and web forms and is primarily disseminated via exploit kits. It was last present in the Top 10 Malware list on October 2017.