An Advance Backdoor called “Stantinko” Installed More than half Million Computer Around the World which Automatically injects Malicious ads Through Browser Extension while surfing on the internet and Create a Backdoor in Victims Computer.
Stantinko has Capable of highly obfuscated and initially it Doesn’t Look Malicious and it looks pretty benign.
A trick used to avoid detection is to hide the malicious code in the Windows Registry.Again, the file itself looks legitimate if you do not have access to the content of that Registry key.
Malware Authors used this Backdoor for performing searches on Google and a tool that brute-forces Joomla and WordPress administrative login pages.
It used Encrypted communication to Communicate with C&C Server and component names Similar to the Domain name. Ex, abc.com similar as abc.dll.
According to ESET Report, Stantinko botnet activity since 2012 and last five years it has increased its Sophisticated level and they are still really active as they released new versions of their main services in March, 2017.
Timeline of the Stantinko services
After completing the Further investigations,requests received from 140,000 unique IP addresses and it is clear from the statistics that the countries mainly targeted are Russia, Ukraine, Belaru, and Kazakhstan.
Browser Extensions Installation
Stantinko‘s one of the main activities is installed the malicious browser extensions which is performing to inject Backdoor in Victims Machine.
Mostly it seems a legitimate Extension and most of the installations were achieved without user consent.
The two browser extensions that installed by Stantinko are The Safe Surfing and Teddy Protection. At the time of writing, both extensions have around 500,000 users.
Number of users of The Safe Surfing & Teddy Protection
In terms of Obfuscation ,Stantinko’s recent components, the code is highly obfuscated with what seems to be a custom obfuscator. Not everything in Stantinko’s toolset is obfuscated, but all PE files that are written to the disk are subject to obfuscation.
According to ESET Research, some of the key findings from our research:
•Installation statistics show that about half a million computers are compromised
•This threat targets mainly Russia (46%) and Ukraine (33%).
•The botnet is monetized by installing browser extensions that inject ads while surfing
•Components that are left on disk employ a custom code obfuscator that mangles strings
and applies control flow flattening.
•In most of the Stantinko components, the malicious code is concealed inside legitimate
free and open source software that has been modified and recompiled.
•Stantinko installs multiple persistent services that install one another to resist cleaning
•Although its most common use is to install adware, Stantinko can actually download
and execute anything. We saw additional modules being deployed on subsets of the botnet
such as a fully-featured remote administration backdoor, a bot performing searches
on Google and a tool that brute-forces Joomla and WordPress administrative login pages.