Top 10 Malware April 2019

The malware variants comprising the Top 10 Malware list for April 2019, is consistent with the previous month’s list. In April, there was simply a shift in the proportion of activity that each malware accounts for. It should be noted that the proportion of Top 10 Malware to Total Malware activity rose above 60% for the first time since last year. Top 10 Malware activity accounts for 64% of Total Malware notifications in April, a 7% increase from March.


In April 2019, malspam is the primary initiation vector for malware in the Top 10 malware list. Both the dropped and network initiation vectors decreased in activity, while malware distributed via multiple vectors increased. An increase in Trickbot infections led to the increased in activity within the multiple category. After February, the malvertisement vector returned to its previous levels of non-activity, as no malware using this vector made it to the Top 10 list.


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 Qakbot 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 Emotet.

Network – Malware introduced through the abuse of legitimate network protocols or tools, such as SMB protocol or remote PowerShell. WannaCry spreads across the Internet via SMB exploits.

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


  1. 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.
  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. 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.
  4. 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.
  5. 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.
  6. 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.
  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. 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.
  9. Emotet is a modular infostealer that downloads or drops banking trojans. It can be delivered through 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. In December 2018, Emotet was observed using a new module that exfiltrates email content
  10. Qakbot is financial malware designed to target governments and businesses for financial fraud and known for its wormability on a network. Qakbot installs a keylogger to steal user credentials. It monitors network traffic, specifically traffic to online banking websites and can piggyback on a user’s active banking session by intercepting authentication tokens. It is currently being dropped by Emotet.