self delete

rule:
  meta:
    name: self delete
    namespace: anti-analysis/anti-forensic/self-deletion
    authors:
      - michael.hunhoff@mandiant.com
      - "@mr-tz"
    scopes:
      static: function
      dynamic: span of calls
    att&ck:
      - Defense Evasion::Indicator Removal::File Deletion [T1070.004]
    mbc:
      - Defense Evasion::Self Deletion::COMSPEC Environment Variable [F0007.001]
    examples:
      - Practical Malware Analysis Lab 14-02.exe_:0x401880
  features:
    - and:
      - or:
        - match: get COMSPEC environment variable
        - string: "cmd.exe"
        - match: host-interaction/process/create
      - or:
        - string: /\/c\s*\bdel\b\s*/
          description: "/c del"
        - string: /(^|[\&;\|]\s*)\bdel\b(\s.*)?/i
          description: "echo 1&&del /path/to/file"
      - optional:
        - string: /\s*>\s*nul\s*/i
          description: "> nul"