Ukraine’s Computer Emergency Response Team (CERT) has issued a warning regarding a recent phishing campaign orchestrated by the Russian state-sponsored threat actor APT28, also known as Fancy Bear or Strontium. This cyber attack, which occurred between December 15 and 25, 2023, targeted Ukraine and involved the deployment of sophisticated malware within an hour.
APT28 is notorious for its focus on government entities, businesses, universities, research institutes, and think tanks in Western countries and NATO organizations. The group employs phishing campaigns and exploits zero-day vulnerabilities in widely used software as part of its modus operandi. The phishing emails in this particular campaign urged recipients to click on a link, ostensibly to access an important document.
However, clicking on the link redirected victims to malicious web resources that utilized JavaScript to drop a Windows shortcut file (LNK). This LNK file initiated a chain of infection, launching PowerShell commands to introduce a new Python malware downloader named ‘MASEPIE.’ MASEPIE, after establishing persistence on the infected device through Registry modifications and deceptive LNK files, played a central role in downloading additional malware and stealing data.
The APT28 attack also involved the use of specific tools, such as ‘STEELHOOK’ PowerShell scripts, designed to extract sensitive data from Chrome-based web browsers. Meanwhile, ‘OCEANMAP,’ a C# backdoor, facilitated stealthy command execution through the Internet Message Access Protocol (IMAP). This allowed the attackers to discreetly receive and execute commands, storing results in email drafts to avoid detection.
The rapid deployment of these tools within an hour of the initial compromise underscores the well-coordinated and swift nature of the cyber onslaught, showcasing the advanced capabilities of the threat actor.
