Banks in Russia today were the target of a massive phishing campaign Attack.Phishing that aimed to deliver a tool used by the Silence group of hackers . The group is believed to have a background in legitimate infosec activities and access to documentation specific to the financial sector . The fraudulent emails purported to come Attack.Phishing from the Central Bank of Russia ( CBR ) and contained a malicious attachment . The message body lured Attack.Phishing the recipients to open the attachment in order to check the latest details on the `` standardization of the format of CBR 's electronic communications . '' Email authentication mechanism saves the day International cybersecurity company Group-IB investigated the attack and noticed that the style and format of the fake communication were very similar to the official CBR correspondence . This supports the theory that the attackers had access Attack.Databreach to legitimate emails from CBR . If Silence hackers have any ties with the legal side of reverse engineering and penetration testing , it is very likely that they are familiar with the documentation used by financial institutions and with how banking systems work . In a report published today , Group-IB says that the attackers spoofed Attack.Phishing the sender 's email address but the messages did not pass the DKIM ( DomainKeys Identified Mail ) validation . DKIM is a solution specifically designed to prevent forged email addresses by adding to the message a signature that confirms its authenticity . Banks see more spear-phishing Attack.Phishing from a different group The Silence hackers are not the only ones trying their spear-phishing Attack.Phishing game on Russian banks . On October 23 , another notorious group , MoneyTaker , ran a similar campaign against the same type of targets . Their message spoofed Attack.Phishing an email address from the Financial Sector Computer Emergency Response Team ( FinCERT ) and contained five attachments disguised as Attack.Phishing documents from CBR . `` Three out of five files were empty decoy documents , but two contained a download for the Meterpreter Stager . To carry out the attack , hackers used self-signed SSL certificates , '' says Rustam Mirkasymov , Group-IB Head of Dynamic Analysis of malware department and threat intelligence expert . These clues , along with server infrastructure associated with the MoneyTaker group , allowed the security experts to identify the perpetrator . As in the case of Silence , this attacker is also thought to have had access Attack.Databreach to CBR documents , most likely from compromised inboxes of Russian banks employees . This allowed them to craft Attack.Phishing messages that would pass even eyes trained in spotting fraudulent emails . Silence and MoneyTaker are the most dangerous threats to banks According to Group-IB , multiple groups use the Central Bank of Russia in spear-phishing Attack.Phishing operations , and for good reason , since the organization dictates regulations to financial institutions in the country and maintains a constant communication flow with them . Mirkasymov says that Silence and MoneyTaker are the most dangerous of all groups that threaten financial organizations . Referring to the latter , the expert says that its repertoire also includes drive-by attacks and testing the network for vulnerabilities . The goal is to access the internal nodes that enable them to withdraw money from ATMs , process cards or interbank transfers . Although Silence uses mainly phishing Attack.Phishing , they are more careful about crafting Attack.Phishing the message , paying attention to both content and design , adds Group-IB 's threat intelligence expert .