DOWNAD Malware using Dictionary Attack to Control the Servers & Remotely Execute Code

A Banking Trojan called DOWNAD has been discovered after 9 years that is capable of remotely inject malicious code into a server and also performing Dictionary Attack which is Considering as one of world’s most prevalent malware.

DOWNAD Malware family first Discovered in 2008 it managed to be one of the most destructive malware at the time, infecting up to 9 million computers.

This DOWNAD family still listed as one of the top malware which has estimated around 2,564,618 detections across the globe.

It has to evolve and increase its infection ratio each and every year since 2012 especially  2015 and 2016 year infection calculated around 0.30M to 0.33M endpoint systems.

According to Trend Micro report, DOWNAD from 2016 and 2017, shows a consistency over time — the malware has stayed above 20,000 monthly detections for both years, which means that in terms of detections, it is still highly active.

Government, manufacturing, and healthcare Industries are the major targets for this DOWNAD Malware.

Major affected countries are notably in the BRICS bloc — India, China, Brazil and these countries manufacturing sectors are mostly affected industries.

How Does DOWNAD Malware Performing Dictionary Attack

Initially, Once its infected the user’s  machine, WORM_DOWNAD.AD first drop its copy into all drivers recycle Bins which is connected to the infected machine’s removable and network drives.

In old version of windows, it used to create obfuscated AUTORUN.INF into all the drivers which are capable of executing whenever a user browses an infected network folder and since this vulnerability has been fixed in new version of windows, it won’t works in the current version of Windows.

Later it will perform to retrieve the user account data from the connected systems by enumerating the available servers on a network.

Once it compromises the network then it will perform a dictionary attack which is having predefined passwords.

WORM_DOWNAD.AD will modify the computer’s DNS settings to prevent the used visiting antivirus-related websites that contain specific strings.

Finally, it will exploit the CVE-2008-4250 vulnerability to the victim’s computer that will allow attackers to remotely execute code on the target’s system.

“Given WORM_DOWNAD.AD’s ability to propagate via multiple avenues, it’s not surprising that the malware manages to still be relevant, 9 years after its peak. Given that we know which detection of DOWNAD is the most prevalent, let’s delve deeper into where exactly the worm can be found,” Trend Micro said.