Malicious Shell Payload Piped from curl to zsh

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.004Unix Shell
Persistence
Priv Esc
Defense Evasion
- T1140Deobfuscate/Decode Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a base64 decoded command that pipes remote content fetched with curl directly into the zsh interpreter. This fileless macOS execution technique is used by fake software advertisement campaigns to run a stealer without touching disk.

Reporting behind it

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Malicious Shell Payload Piped from curl to zsh

Pivot detection · T1140 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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