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Home/ATT&CK/Software/S0221
MITRE ATT&CK Malware

Umbreon (S0221)

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A Linux rootkit that provides backdoor access and hides from defenders.

Platforms: Linux

▪Techniques implemented (5)

T1059.003Windows Command ShellT1014RootkitT1205Traffic SignalingT1095Non-Application Layer ProtocolT1078.003Local Accounts
S0221on MITRE ATT&CK →

MITRE ATT&CK® is a registered trademark of The MITRE Corporation. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation.