[Raindrop](https://attack.mitre.org/software/S0565) is a loader used by [APT29](https://attack.mitre.org/groups/G0016) that was discovered on some victim machines during investigations related to the [SolarWinds Compromise](https://attack.mitre.org/campaigns/C0024). It was discovered in January 2021 and was likely used since at least May 2020.(Citation: Symantec RAINDROP January 2021)(Citation: Microsoft Deep Dive Solorigate January 2021)