Suspicious Delayed Expansion Command Obfuscation Building PowerShell via Amatera Stealer

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1027.010Command Obfuscation
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects cmd.exe using delayed variable expansion to concatenate fragmented strings that reassemble the word powershell at runtime. The Amatera Stealer 4.0.2 loader splits pow and ershell across set commands to defeat static string matching before invoking an encoded PowerShell stage. This command-line obfuscation is a strong indicator of staged stealer execution.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

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Suspicious Delayed Expansion Command Obfuscation Building PowerShell via Amatera Stealer

Pivot detection · T1059.001 · 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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