Detectionhighexperimental

Suspicious Download and Execute Pattern via Curl/Wget

Detects suspicious use of command-line tools such as curl or wget to download remote content - particularly scripts - into temporary directories (e.g., /dev/shm, /tmp), followed by immediate execution, indicating potential malicious activity. This pattern is commonly used by malicious scripts, stagers, or downloaders in fileless or multi-stage Linux attacks.

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Launch

Aayush GuptaCreated Tue Jun 17a2d9e2f3-0f43-4c7a-bcd9-9acfc0d723aalinux

Log Source

LinuxProcess Creation

ProductLinux← raw: linux

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection_downloader:
        CommandLine|contains:
            - '/curl'
            - '/wget'
    selection_tmp:
        CommandLine|contains:
            - '/tmp/'
            - '/dev/shm/'
    selection_executor:
        CommandLine|contains: 'sh -c'
    condition: all of selection_*