Mac Backdoors Leveraging Firefox Zero-Day Vulnerability

New variants of two backdoors, Netwire and Mokes, have been observed leveraging a zero-day vulnerability in the Mozilla Firefox web browser to infect macOS devices.

Threat ID:: CC-3130
Category:
Threat Severity:: Low
Threat Vector:
Published:: 4 July 2019 12:00 AM

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

Summary

New variants of two backdoors, Netwire and Mokes, have been observed leveraging a zero-day vulnerability in the Mozilla Firefox web browser to infect macOS devices.

Affected platforms

The following platforms are known to be affected:

Mozilla Firefox

Apple MacOS - All versions

Mozilla Firefox - Versions prior to Firefox 67.0.3
Mozilla Firefox ESR - Versions prior to 60.7.1

Mozilla Firefox ESR

Threat details

Both backdoors are delivered via email containing links to a malicious site. When a user browses to the site using a vulnerable version of Firefox, the vulnerability is exploited to downloaded the malware. By leveraging this vulnerability the malware is able to bypass some of the security features built-in to macOS. Once deployed on a user's system, the backdoors persist as launch agents so that the malware is loaded each time the user logs in.

Both observed variants allow an attacker to execute arbitrary commands, take screenshots and steal system information from an infected machine. In addition, the Mokes variant has the capability to capture audio and video, steal documents and record keystrokes.

For further information:

CVE-2019-11707

Remediation steps

Type	Step
	To prevent and detect an infection by Netwire or Mokes, ensure that: Users and administrators are encouraged to review the Mozilla Security Advisory for Firefox and apply the necessary updates. 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. Regular anti-virus and security scans are performed on your organisation’s estate. 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

To prevent and detect an infection by Netwire or Mokes, ensure that:

Users and administrators are encouraged to review the Mozilla Security Advisory for Firefox and apply the necessary updates.
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.
Regular anti-virus and security scans are performed on your organisation’s estate.
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.

CVE Vulnerabilities

Status

CVE-2019-11707

Last edited: 14 February 2020 2:50 pm