[GrimAgent](https://attack.mitre.org/software/S0632) is a backdoor that has been used before the deployment of [Ryuk](https://attack.mitre.org/software/S0446) ransomware since at least 2020; it is likely used by [FIN6](https://attack.mitre.org/groups/G0037) and [Wizard Spider](https://attack.mitre.org/groups/G0102).(Citation: Group IB GrimAgent July 2021)
Platforms: Windows
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