[Poseidon Group](https://attack.mitre.org/groups/G0033) is a Portuguese-speaking threat group that has been active since at least 2005. The group has a history of using information exfiltrated from victims to blackmail victim companies into contracting the [Poseidon Group](https://attack.mitre.org/groups/G0033) as a security firm. (Citation: Kaspersky Poseidon Group)
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