In June 2021, the MS-ISAC observed BitCoin Miner, Mirai, and Ursnif’s return to the Top 10. The Top 10 Malware variants comprise 62% of the total malware activity in June 2021, decreasing 13% from May 2021. Slayer is likely to continue its prevalence in the Top 10 Malware for the coming quarter. However, a recent patch from Apple addresses a zero-day vulnerability Shlayer used. This is likely reducing its effect, as we saw a 57% decrease in infections from the previous month.

In June 2021, malvertisement accounted for the greatest number of alerts. Malvertisement continues as the top initial vector due to Shlayer activity. Activity levels for dropped increased, while activity for malspam, malvertisement, and multiple decreased.

Dropped – Malware delivered by other malware already on the system and exploited kit, infected third-party software, or manually by a cyber threat actor.

Multiple – Malware that currently favors at least two vectors. Currently, BitCoin Miner, CoinMiner, CryptoWall, and ZeuS are malware utilizing multiple vectors.

Malspam – Unsolicited emails, which either direct users to malicious websites or trick users into downloading or opening malware.

Malvertisement – Malware is introduced through malicious advertisements. Currently, Shlayer is the only Top 10 Malware using this technique.

Top 10 Malware and IOCs

1. Shlayer

Shlayer is a downloader and dropped for MacOS malware. It is primarily distributed through malicious websites, hijacked domains, and malvertizing posing as a fake Adobe Flash updater.

2. CoinMiner

CoinMiner is a cryptocurrency miner that uses Windows Management Instrumentation (WMI) and EternalBlue to spread across a network. It takes advantage of outdated versions of SMB.

3. Miria

Mirai is a botnet known to compromise internet of things (IoT) devices in order to conduct large-scale DDoS attacks. Mirai is dropped after an exploit has allowed the attacker to gain access to a machine.

4. NanoCore

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.

5. Quasar

Quasar is an open-source remote administration tool on the Windows Platform. It is used as a RAT to create backdoors.

6. ZeuS

ZeuS is a modular banking trojan that used keystrokes logging to compromise victim credentials when the user visits a banking website.

7. Gh0st

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. BitCoin Miner

BitCoin Miner is a cryptocurrency miner that uses your computer’s resources to set up bitcoin blocks and forward them to a remote server.

9. Ursnif

Ursnif, and its variants Dreambot, are banking trojans known for weaponizing documents. Ursnif recently upgraded its web injection attacks to include TLS callbacks in order to obfuscate against anti-malware software. Ursnif collects victim information from login pages and web forms.

10. CryptoWall

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.

Interested in reading more about malware in 2021? TrickBot – A Malware with Multiple Hats in 2021 discusses malware known as ‘TrickBot’ and how it is affecting millions.

MalwareIf you would like TSVMap to assist your business with assessing your essential systems and applying the TSVMap methodology to ERP SystemsMRP SystemsCyber SecurityIT StructureWeb ApplicationsBusiness Operations, and Automation, please contact us at 864-991-5656 or