Malicious macOS Payload Decryption via openssl with Password

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
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 openssl decrypting a base64-encoded payload using an explicit password, the runtime deobfuscation step observed in newer macOS Bundlore variants. Attackers decode an encrypted shell stage before piping it to system() so the payload never appears in cleartext on disk.

Reporting behind it

Related detections9 linkedT1140 — drag to rearrange

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Suspicious PowerShell Payload Extraction from PNG Polyglot via findstr

Suspicious Python Inline Deobfuscation and Execution One-Liner

Suspicious Base64 Decoded Payload Piped to Shell on Linux

Malicious macOS Payload Decryption via openssl with Password

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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