InfraGuard

Detection rule: Unexpected Protocol

A protocol that cannot legitimately appear in this session.

CriticalProtocol AnomalySuricata

What it detects

A protocol that cannot legitimately appear in this session.

Why it fires

Possible port masquerading, tunneling or C2 covert channel.

Worst case

C2 covert channel

Matching signatures

unexpected protocol

Track these versions on your own servers

InfraGuard collects installed software versions from every server and flags the ones with known vulnerabilities. Self-hosted — nothing leaves your network.

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