Detectionhightest

Suspicious Invocation of Shell via AWK - Linux

Detects the execution of "awk" or it's sibling commands, to invoke a shell using the system() function. This behavior is commonly associated with attempts to execute arbitrary commands or escalate privileges, potentially leading to unauthorized access or further exploitation.

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Launch

Li Ling, Andy Parkidomo, Robert Rakowski, Blake Hartstein (Bloomberg L.P.)Created Mon Sep 028c1a5675-cb85-452f-a298-b01b22a51856linux

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_img:
        Image|endswith:
            - '/awk'
            - '/gawk'
            - '/mawk'
            - '/nawk'
        CommandLine|contains: 'BEGIN {system'
    selection_cli:
        CommandLine|contains:
            - '/bin/bash'
            - '/bin/dash'
            - '/bin/fish'
            - '/bin/sh'
            - '/bin/zsh'
    condition: all of selection_*