Analyzing Forest Blizzard’s custom post-compromise tool for exploiting CVE-2022-38028 to obtain credentials

From microsoft.com

Microsoft Threat Intelligence is publishing results of our longstanding investigation into activity by the Russian-based threat actor Forest Blizzard (STRONTIUM) using a custom tool to elevate privileges and steal credentials in compromised networks. Since at least June 2020 and possibly as early as April 2019, Forest Blizzard has used the tool, which we refer to as GooseEgg, to exploit the CVE-2022-38028 vulnerability in Windows Print Spooler service by modifying a JavaScript constraints file and executing it with SYSTEM-level permissions. Microsoft has observed Forest Blizzard using GooseEgg as part of post-compromise activities against targets including Ukrainian, Western European, and North American government, non-governmental, education, and transportation sector organizations. While a simple launcher application, GooseEgg is capable of spawning other applications specified at the command line with elevated permissions, allowing threat actors to support any follow-on objectives such as remote code execution, installing a backdoor, and moving laterally through compromised networks.

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