Cybersecurity researchers have uncovered a sophisticated cyberattack campaign utilizing phishing emails to deliver a malicious software known as SSLoad. This malware is part of a broader operation dubbed FROZEN#SHADOW by Securonix, which leverages both Cobalt Strike—a legitimate security tool repurposed by attackers—and ConnectWise ScreenConnect software for remote desktop control. The phishing emails used in this campaign typically include links that prompt the download of a JavaScript file, initiating the infection process that eventually leads to the installation of SSLoad. This malware is particularly dangerous as it is designed to stealthily infiltrate systems, gather sensitive data, and establish persistent access while evading detection.
Once SSLoad is installed on the victim’s system, it sets about executing multiple backdoor functionalities and downloading additional payloads. This allows the attackers to maintain a hidden presence on the system, collecting sensitive information and preparing the ground for further malicious activities. The malware facilitates a comprehensive reconnaissance phase that gathers critical system details and scans for stored credentials and potentially sensitive documents. The end goal is to fully map the network environment and identify further targets within the victim’s infrastructure.
The attack does not stop at initial access and data harvesting. With SSLoad and Cobalt Strike installed, attackers proceed to download and install ScreenConnect, granting them remote control over the infected host. This capability allows for deep lateral movement within the network, including access to significant network nodes like domain controllers. In some cases, the attackers have been observed creating new domain administrator accounts, giving them the same level of access as legitimate network administrators, which enables them to access any connected machine within the domain.
This level of intrusion is catastrophic for organizations as it allows attackers to operate as if they are legitimate administrators, making detection and remediation extremely challenging and costly. The campaign targets organizations randomly across Asia, Europe, and the Americas, demonstrating its global reach and the indiscriminate nature of its targets. To protect against such threats, organizations are advised to be vigilant about phishing attempts, strengthen their email security protocols, and continuously monitor and update their network security measures to defend against evolving cyber threats.
