CVE-2022-38028 is a critical vulnerability in the Windows Print Spooler service that allows for arbitrary code execution with elevated privileges. The exploit was addressed by Microsoft in a security update released on October 11, 2022. More details on this vulnerability can be found on the Microsoft Security Update Guide.

Tactics and Techniques of Forest Blizzard

Forest Blizzard, identified as a Russian-based threat actor affiliated with the GRU, has been utilizing a custom tool, dubbed ‘GooseEgg’, to exploit CVE-2022-38028. This tool facilitates privilege escalation and credential theft within compromised networks. GooseEgg operates by manipulating JavaScript files to execute with SYSTEM-level permissions, an attack method that highlights the actor’s sophistication and focus on stealth and persistence within target systems.

Attack Implications

The primary objective of GooseEgg is to gain elevated access and exfiltrate sensitive information from target organizations, which commonly include governmental and non-governmental bodies in Europe, North America, and the Middle East. The exploitation of CVE-2022-38028 by Forest Blizzard is part of a broader strategy to support Russian governmental foreign policy goals and intelligence gathering operations.

Mitigation and Defense Strategies

Organizations are advised to apply the security updates provided by Microsoft for CVE-2022-38028 promptly. Additional protective measures include:

  • Disabling the Print Spooler service where not necessary, especially on servers.
  • Implementing endpoint detection and response (EDR) systems.
  • Enforcing the principle of least privilege and segmenting networks to limit lateral movement.

Indicators of Compromise and Detection Techniques

Key indicators include the use of specific batch scripts (e.g., execute.bat, doit.bat) and unusual scheduled tasks. Organizations should monitor for alterations to JavaScript files within the Windows Print Spooler directory and registry changes that facilitate the persistence of malicious DLLs.

For further information, Microsoft’s security blog provides an in-depth analysis of the tools and methods employed by Forest Blizzard using GooseEgg: Microsoft Security Blog.

Further Reading