ZeroAccess Trojan

ZeroAccess is a stealthy trojan which has been infecting systems since at least 2011. The trojan affects Microsoft windows operating systems.

Threat ID:: CC-1513
Category:: Botnet, Rootkit, Trojan
Threat Severity:: Medium
Threat Vector:
Published:: 11 July 2017 12:00 AM

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Summary

ZeroAccess is a stealthy trojan which has been infecting systems since at least 2011. The trojan affects Microsoft windows operating systems.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - all versions

Threat details

ZeroAccess is used to download other malware onto an affected hosts using a botnet that had previously been associated with Bitcoin mining and click fraud. It is designed to remain undetected on targeted systems using rootkit techniques.

Upon initial infection, ZeroAccess overwrites the Windows core system files and installs Kernel Hooks in an attempt to remain stealthy. Once the hooks are installed, the operating system falls into the control of the rootkit which is then able to hide process, files and network activity as well as attempting to kill any security software trying to access the trojan's processes or files.

The primary purpose of the malware appears to be revenue generation through pay-per-click advertising. However, ZeroAccess, a back door is installed to allow connections to a command and control server. This provides a remote attacker with full access to the compromised system.

Threat updates

Date	Update
26 Mar 2018	ZeroAccess has been updated to mine cryptocurrency mining.

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, applications, antivirus 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 and that permissions are always assigned on the basis of least privilege. 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, applications, antivirus 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 and that permissions are always assigned on the basis of least privilege.
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 11:42 am