Security experts at Malwarebytes observed an adware campaign that involved the Extembro DNS-
“Recently, we uncovered a new DNS-changer called Extenbro that comes with an adware
The Extenbro Trojan is used to change the DNS settings, victims can only notice that it adds four DNS servers to the Advanced DNS tab in Windows.
To malware gain persistence by creating a randomly-named Scheduled Task that points to a fixed-location folder.
The Extenbro Trojan adds a certificate to the set of Windows Root certificates, it has no “Friendly Name” and experts believe it was registered to
The malware also disables IPv6 by changing the registry value DisabledComponents under the key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\TCPIP6\Parameters. Thus, it forces the system to use the new DNS servers.
On top of that, the Trojan makes a change in the Firefox user
The Extenbro Trojan also modifies the Firefox user
The analysis published by Malwarebytes includes the removal instructions.
To restore their DNS settings, users should remove the DNS entries added by the malware from the DNS advanced settings without rebooting the system.
“To get to your security sites, you may need a restart of the browser. Do NOT reboot your system or the DNS servers might be changed for the worse again by the Scheduled Task that belongs to the Trojan. If your existing solution does not pick up on the malware, download Malwarebytes to your desktop.” concludes the analysis.
To restore Firefox to the initial settings, users should type