Security experts from Kaspersky lab discovered a new trojan dubbed Silence trojan that targeting Financial institutions. It was first spotted September this year and they are primarily targetting Russian banks.
Attackers beyond Silence Trojan using spear-phishing methods as an initial attack vector to gain access to the bank network.
Once they gained a persistent access to bank networks they record day to day activity of bank employees’ PCs and gather as much as possible information to loot money.
Also Read Dangerous Crypto Currency Mining Malware Apps Found on Google Play Store
How does it work – Silence Trojan
Attackers distributing trojans with spear-phishing emails using employees email address of the organization that compromised already by requesting to open an account in the bank.
Kaspersky researchers spotted a compiled HTML file(CHTML) in the attachment which is highly interactive and contains Javascript which redirects the victim to external URL after opening the CHM file.
The end goal of the script is to download and execute obfuscated.VBS script which then downloads the final dropper.
Payload Communication
Then dropper executes and connects with C&C server and downloads the payload, which is capable of performing various tasks like screen recording, data uploading etc. The main task of the payload is to monitor the victim’s activity.
In order to do so, it takes multiple screenshots of the victim´s active screen, providing a real-time pseudo-video stream with all the victim´s activity. A very similar technique was used in the Carbanak case, where this monitoring was used to understand the victim´s day to day activity.Researchers said.
Hackers targeting financial organizations to make money, you can find the detailed analysis with Kaspersky’s blog. It is evident still spear-phishing infection vector is the most popular way.
IOC’s
Backdoor.Win32.Agent.dpke
Backdoor.Win32.Agent.dpiz
Trojan.Win32.Agentb.bwnk
Trojan.Win32.Agentb.bwni
Trojan-Downloader.JS.Agent.ocr
HEUR:Trojan.Win32.Generic