FBI: Phishing emails are spreading this sophisticated malware

Alert by the FBI and CISA warns that Trickbot - one of the most common and most powerful forms of malware around - is using a new trick in an effort to infect even more victims.
Written by Danny Palmer, Senior Writer

A new spear-phishing campaign is attempting to infect PCs with Trickbot, one of the most prevalent and potent forms of malware around today, a joint advisory from the FBI and the Cybersecurity and Infrastructure Security Agency (CISA) has warned.

Trickbot started life as a banking trojan but has become one of the most powerful tools available to cyber criminals, who are able to lease out access to infected machines in order to deliver their own malware – including ransomware.

Now its authors are using a new tactic to attempt to deliver it to victims, warns the joint FBI and CISA alert phishing emails that claim to contain proof of a traffic violation. The hope is that people are scared into opening the email to find out more.

SEE: A winning strategy for cybersecurity (ZDNet special report) | Download the report as a PDF (TechRepublic)

The malicious email contains a link that sends users to a website hosted on a server compromised by the attackers that tells the victim to click on a photo to see proof. When they click the photo, they actually download a JavaScript file that, when opened, connects to a command and control server that will download Trickbot onto their system.

Trickbot creates a backdoor onto Windows machines, allowing the attackers to steal sensitive information including login credentials, while some versions of Trickbot are capable of spreading across entire networks.

The modular nature of Trickbot means it's highly customisable, with additional attacks by the malware known to include dropping further malware – such as Ryuk or Conti ransomware – or until recently, serving as a downloader for Emotet malware. Trickbot is also able to exploit infected machines for cryptomining.

A coalition of cybersecurity companies attempted to disrupt Trickbot in October last year, but the malware didn't stay quiet for long, with its cyber-criminal authors quickly able to resume their operations.

"The takedown efforts in October were unlikely to permanently disrupt or disable this very capable commodity malware that has been active on the threat landscape at scale for years. It has a strong infrastructure and the ability to continue operating," Sherrod DeGrippo, senior director of threat research and detection at Proofpoint told ZDNet.

"To completely remove Trickbot from the landscape would be extremely difficult and likely require a coordinated international law enforcement effort like we saw with Emotet. In fact, after the actions of October 2020, we saw Trickbot campaigns resume within weeks, and it has been active continually since," she added.

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Trickbot remains a powerful tool for cyber criminals and a clear danger for enterprises and organisations of all sizes – but there are measures recommended by CISA and the FBI that can be taken in order help protect networks from the malware.

Providing social-engineering and phishing email training to employees can help them to avoid threats by being wary of certain types of messages.

Organisations should also be implementing a proper cybersecurity programme with a formalised security patch management process, so cyberattacks can't exploit known vulnerabilities to gain a foothold on the network. It's also recommended that multi-factor authentication is applied across the enterprise, so malware that steals login credentials to move across the network can't do so as easily.


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