Suspicious Shell Command Obfuscation via printf Escape Encoding on VMware ESXi (via process_creation)

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
- T1140Deobfuscate/Decode Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects shell commands on VMware ESXi that reconstruct strings through printf hex or octal escape sequences before executing infrastructure utilities. Threat actors encode esxcli and shell invocations this way to evade keyword-based detection. A printf escape construct combined with an esxcli or shell target is a strong obfuscation signal.

Reporting behind it

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Suspicious Shell Command Obfuscation via printf Escape Encoding on VMware ESXi (via process_creation)

Pivot detection · T1027 · 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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