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Top 10 Malware October 2019

The composition of the Top 10 Malware in October remains mostly consistent with the previous month with Emotet once again joining the mix. Top 10 Malware comprised 72% of Total Malware activity in October, indicating the Top 10 Malware variants are driving the rate of malware infections. Emotet and subsequent TrickBot infections drove the majority of activity for the month making up a combined 40% of all malware notifications.
In October 2019, malware utilizing multiple initiation vectors accounted for the greatest number of alerts in the Top 10 malware list. The sharp increase in the multiple and malspam categories is attributed to the resumed Emotet distribution campaigns as Emotet drops TrickBot onto infected systems. ZeuS and TrickBot infections account for the rise in activity within the multiple infection vector category over the last five months. Emotet, Dridex, Kovter, Ursnif, and NanoCore drive the increase in malspam related infections for the month of October. There is a high likelihood that malspam will continue to remain elevated with the resumption of Emotet distribution campaigns.
October-2019-MS-ISAC-Malware-Notifications.png
October-2019-Malware
In October 2019, malware utilizing multiple initiation vectors accounted for the greatest number of alerts in the Top 10 malware list. The sharp increase in the multiple and malspam categories is attributed to the resumed Emotet distribution campaigns as Emotet drops TrickBot onto infected systems. ZeuS and TrickBot infections account for the rise in activity within the multiple infection vector category over the last five months. Emotet, Dridex, Kovter, Ursnif, and NanoCore drive the increase in malspam related infections for the month of October. There is a high likelihood that malspam will continue to remain elevated with the resumption of Emotet distribution campaigns.
October-2019-Infection-Vectors

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 is being dropped.

Multiple – Malware that currently favors at least two vectors. TrickBot, ZeuS, and CryptoWall 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 vector include Emotet, Dridex, Kovter, NanoCore, Tinba, and Cerber.

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

  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. 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.
  3. ZeuS is a modular banking trojan that 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.
  4. 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.
  5. 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.
  6. CryptoWall is ransomware commonly distributed through malspam with malicious ZIP attachments, Java Vulnerabilities, and malicious advertisements. Upon successful infection, CryptoWall will scan the system for drive letters, network shares, and removable drives. CryptoWall runs on both 32-bit and 64-bit systems.
  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. 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. 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 June 2019
  10. Cerber is evasive ransomware that is capable of encrypting files in offline mode and is known for fully renaming files and appending them with a random extension. There are currently six versions of Cerber, which evolved specifically to evade detection by machine learning algorithms. Currently, version 1 is the only version of Cerber for which a decryptor tool is available.