Sandworm (Unit 74455 / Seashell Blizzard)

Sandworm is Russia's most destructive cyber unit, responsible for the most damaging cyberattacks ever recorded.

Threat IntelligenceTIDThreatIntermediateCONFIDENTIAL2,172 words9 min readApr 7, 2026

Last updated Apr 11, 2026v2

CLASSIFICATION: CONFIDENTIAL

This article requires CONFIDENTIAL clearance or higher.

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Table of Contents

Sandworm (Unit 74455 / Seashell Blizzard)

What you need

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