In-memory Downloading and Compiling of Applets as Payloads
This analytic uses a single ES_EVENT_TYPE_NOTIFY_EXEC event and looks for the the execution of curl, |, or osacompile commands. Part of the RedCanary 2024 Threat Detection Report.
Sigma rule (View on GitHub)
 1title: In-memory Downloading and Compiling of Applets as Payloads
 2id: 75933b00-4949-4cf0-a0e0-f234c3ff1407
 3status: experimental
 4description: |
 5    This analytic uses a single ES_EVENT_TYPE_NOTIFY_EXEC event and looks for 
 6    the the execution of curl, |, or osacompile commands. Part of the RedCanary 
 7    2024 Threat Detection Report.    
 8references:
 9    - https://redcanary.com/threat-detection-report/techniques/applescript/
10author: RedCanary, Sigma formatting by Micah Babinski
11date: 2024/03/21
12tags:
13    - attack.execution
14    - attack.t1059
15    - attack.t1059.002
16logsource:
17    product: macos
18    category: process_creation
19detection:
20    selection:
21        CommandLine|contains|all:
22            - 'osascript'
23            - '|'
24            - 'curl'
25    condition: selection
26falsepositives:
27    - Unknown
28level: low```
References
Related rules
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