Lace Tempest Cobalt Strike Download via PowerShell
This rule detects a specific command-line execution pattern used by the threat actor 'Lace Tempest' to download 'Cobalt Strike'. The pattern involves PowerShell's 'IEX ((new-object net.webclient).downloadstring(' command, which is commonly used for in-memory execution of downloaded scripts or payloads. The detection specifically looks for the combination of '-nop -w hidden -c IEX ((new-object net.webclient).downloadstring(' and '/a') in the command line, indicating an attempt to download and execute a script, likely a Cobalt Strike payload, as reported by the SysAid Team.
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