Rewterz Threat Update – QakBot Malware Resurfaces, Targeting the Health Sector with New Techniques

Severity

High

Analysis Summary

Microsoft has identified a resurgence of the QakBot malware in a low-volume phishing campaign targeting the hospitality industry. This revival comes more than three months after law enforcement efforts dismantled QakBot’s infrastructure through Operation Duck Hunt. The campaign, which began on December 11, 2023, involves sending PDFs from a fake IRS employee, containing a URL that downloads a digitally signed Windows Installer (.msi). Executing the MSI triggers QakBot through an embedded DLL using the export ‘hvsi’ execution method. Microsoft noted that the payload, configured with the previously unseen version 0x500, was generated on the same day the campaign started.

QakBot, also known as QBot and Pinkslipbot, is notorious for harvesting sensitive information and delivering additional malware, including ransomware. Operation Duck Hunt initially disrupted QakBot by gaining access to its infrastructure and instructing infected computers to download an uninstaller file, rendering the malware ineffective. However, the recent resurgence indicates its resilience.

Similar to the return of Emotet in late 2021, QakBot’s reappearance underscores the challenge of permanently dismantling such botnets. In October 2023, Cisco’s researchers revealed that QakBot affiliates were employing phishing lures to distribute a mix of ransomware, remote access trojans, and stealer malware. The comparison to Emotet, which remains a persistent threat, highlights the ongoing need for organizations to remain vigilant against spam emails associated with these campaigns. While it is uncertain if QakBot will regain its former prominence, the incident emphasizes the importance of cybersecurity measures to mitigate the risks posed by resurgent malware and underscores the need for ongoing vigilance in the face of evolving cyber threats.

Impact

• Sensitive Data Theft
• Unauthorized Access

Remediation

• Implement multi-factor authentication to add an extra layer of security to login processes.
• Regularly monitor network activity for any unusual behavior, as this may indicate that a cyberattack is underway.
• Organizations need to stay vigilant and follow best practices for cybersecurity to protect their systems and data from potential threats. This includes regularly updating software and implementing strong access controls and monitoring tools.
• Develop a comprehensive incident response plan to respond effectively in case of a security breach or data leakage.
• Maintain regular backups of critical data and systems to ensure data recovery in case of a security incident.
• Adhere to security best practices, including the principle of least privilege, and ensure that users and applications have only the necessary permissions.
• Establish a robust patch management process to ensure that security patches are evaluated, tested, and applied promptly.
• Conduct security audits and assessments to evaluate the overall security posture of your systems and networks.
• Implement network segmentation to contain and isolate potential threats to limit their impact on critical systems.