Detectionmediumtest

Linux Base64 Encoded Pipe to Shell

Detects suspicious process command line that uses base64 encoded input for execution with a shell

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Martin MuellerCreated Tue Jul 26Updated Fri Jun 16ba592c6d-6888-43c3-b8c6-689b8fe47337linux
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 Logic2 selectors
detection:
    selection_base64:
        CommandLine|contains: 'base64 '
    selection_exec:
        - CommandLine|contains:
              - '| bash '
              - '| sh '
              - '|bash '
              - '|sh '
        - CommandLine|endswith:
              - ' |sh'
              - '| bash'
              - '| sh'
              - '|bash'
    condition: all of selection_*
False Positives

Legitimate administration activities

Rule Metadata
Rule ID
ba592c6d-6888-43c3-b8c6-689b8fe47337
Status
test
Level
medium
Type
Detection
Created
Tue Jul 26
Modified
Fri Jun 16
Path
rules/linux/process_creation/proc_creation_lnx_base64_execution.yml
Raw Tags
attack.defense-evasionattack.t1140
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