Bateleur JavaScript Backdoor

First observed in 2017, Bateleur is a JavaScript-based backdoor tool created by the Carbanak (also known as FIN7 or Anunak) advanced persistent threat group.

Threat ID:: CC-2574
Category:: Backdoor
Threat Severity:: Medium
Threat Vector:: Email spam
Published:: 7 August 2018 12:00 AM

Report a cyber attack: call 0300 303 5222 or email [email protected]

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Summary

First observed in 2017, Bateleur is a JavaScript-based backdoor tool created by the Carbanak (also known as FIN7 or Anunak) advanced persistent threat group.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - All versions

Threat details

It has been used in targeted campaigns against governmental, financial, health and engineering organisations globally.

Bateleur is typically distributed as a malicious Word document in spam campaigns directed at target organisations, but has also been observed being delivered directly to previously compromised devices. Once opened, macros in the document extract an obfuscated JavaScript payload and save it as debug.txt. Bateleur also has anti-VM capabilities, although these are only enabled in certain variants.

Once installed, Bateleur will connect to a command and control server over HTTPS and await instructions. It is able to collect system and user information, execute commands and PowerShell scripts, install secondary malware and upgrade its functionality with additional modules.

Remediation advice

To prevent and detect an infection, ensure that:

Remediation steps

Type	Step
	A robust program of education and awareness training is delivered to users to ensure they don’t open attachments or follow links within unsolicited emails. All operating systems, anti-virus and other security products are kept up-to-date. All day-to-day computer activities such as email and internet are performed using non-administrative accounts. Strong password policies are in place. Network, proxy and firewall logs should be monitored for suspicious activity. User accounts accessed from affected devices should be reset on a clean computer. Your organisation adopts a holistic all-round approach to Cyber Security as advocated by the 10 Steps to Cyber Security.

Type

Step

A robust program of education and awareness training is delivered to users to ensure they don’t open attachments or follow links within unsolicited emails.
All operating systems, anti-virus and other security products are kept up-to-date.
All day-to-day computer activities such as email and internet are performed using non-administrative accounts.
Strong password policies are in place.
Network, proxy and firewall logs should be monitored for suspicious activity.
User accounts accessed from affected devices should be reset on a clean computer.
Your organisation adopts a holistic all-round approach to Cyber Security as advocated by the 10 Steps to Cyber Security.

Last edited: 17 February 2020 12:38 pm