Postmark Backdoor
Postmark Backdoor is described in the provided content as a backdoor associated with what was reported as the first malicious MCP observed in the wild. The malware is specifically characterized as stealing emails. It is referenced in Security Affairs reporting from October 5, 2025, including the article title “First Malicious MCP in the Wild: The Postmark Backdoor That’s Stealing Your Emails.” No additional high-confidence details are provided in the content regarding its infection vector, technical implementation, targeted platforms, associated threat actor, industries targeted, or indicators of compromise.
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Backdoor malware that steals emails, representing the first malicious instance of MCP observed in the wild.
Backdoor malware that steals emails, noted as the first malicious MCP (Mail Client Plugin) observed in the wild.
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