MirrorBlast phishing campaign targets financial companies

The attack has been linked to a long-standing Russian cyber crime group

A Russian cyber crime group has been targeting the financial sector with malware delivered by a familiar infection mechanism: Microsoft Office macros. 

Security company Morphisec identified the attack, dubbed MirrorBlast, which uses Microsoft Office macros to infect machines, a technique cyber criminals have used consistently over the years. 

The researchers analyzing the attack said it has been underway since September. It targets institutions in regions such as Canada, US, Hong Kong, and Europe. The researchers also saw similar activity in April. 

Morphisec tied the attack to TA505, a Russian cyber crime group that has been operating since 2014. The group often changes the malware it uses, according to the company.

The cyber crime gang uses phishing emails to mount the first phase of its attack. The initial email contains an Excel document that uses a macro. The macro, which can only run on 32-bit systems due to ActiveX compatibility issues, contains lightweight code designed to avoid detection. 

When run, the macro verifies an administrative account is running and then uses a Javascript command to start an installer program. This drops one of two malicious scripts. 

Related Resource

Prevent fraud and phishing attacks with DMARC

How to use domain-based message authentication, reporting, and conformance for email security

Prevent fraud and phishing attacks with DMARC - whitepaper from MimecastFree download

These send the machine's information to a command and control (C2) server, including the computer name, user name, and a list of running processes. The C2 server then responds with a code telling the software how to proceed. 

The attack also uses a Google feedproxy URL with a fraudulent message urging the user to access a SharePoint or Onedrive file. This helps the attackers evade detection, Morphisec said. 

Certain aspects of the attack have led researchers to attribute it to TA505. This includes the infection chain and installer script. It also uses similar domain names to other TA505 attacks and an MD5 hash that matches one used in another of the group's attacks.

Featured Resources

Shining light on new 'cool' cloud technologies and their drawbacks

IONOS Cloud Up! Summit, Cloud Technology Session with Russell Barley

Watch now

Build mobile and web apps faster

Three proven tips to accelerate modern app development

Free download

Reduce the carbon footprint of IT operations up to 88%

A carbon reduction opportunity

Free Download

Comparing serverless and server-based technologies

Determining the total cost of ownership

Free download

Recommended

Education and government most at risk from email threats
phishing

Education and government most at risk from email threats

26 Nov 2021
RATDispenser evades nine in ten anti-virus engines
Security

RATDispenser evades nine in ten anti-virus engines

24 Nov 2021
Hackers use Linux backdoor on compromised e-commerce sites with software skimmer
malware

Hackers use Linux backdoor on compromised e-commerce sites with software skimmer

19 Nov 2021
Iranian hackers ramp up attacks against IT services sector
hacking

Iranian hackers ramp up attacks against IT services sector

19 Nov 2021

Most Popular

How to move Microsoft's Windows 11 from a hard drive to an SSD
Microsoft Windows

How to move Microsoft's Windows 11 from a hard drive to an SSD

24 Nov 2021
What should you really be asking about your remote access software?
Sponsored

What should you really be asking about your remote access software?

17 Nov 2021
Nike to take customers into the metaverse with 'NIKELAND'
virtualisation

Nike to take customers into the metaverse with 'NIKELAND'

19 Nov 2021