Windows: 7-Zip Compressing .dmp/.dump Files

title: "Windows: 7-Zip Compressing .dmp/.dump Files"
id: df54134f-64b8-40fa-8834-32af0605bbec
related:
  - id: 1ac14d38-3dfc-4635-92c7-e3fd1c5f5bfc
    type: derived
  - id: ec570e53-4c76-45a9-804d-dc3f355ff7a7
    type: derived
status: test
description: This rule identifies Windows process executions where 7z.exe (or its variants 7za.exe/7zr.exe) is launched and the command line includes dump-related extensions such as .dmp, .dump, or .hdmp. Compressing dump files can be used to package data for later collection or exfiltration, making it a useful behavior to flag during incident triage. It relies on process creation telemetry, using image/original file name matching for 7-Zip and command line substring matches for the dump extensions.
references:
  - https://thedfirreport.com/2022/09/26/bumblebee-round-two/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_7zip_exfil_dmp_files.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2022-09-27
modified: 2026-06-05
tags:
  - attack.collection
  - attack.t1560.001
logsource:
  category: process_creation
  product: windows
detection:
  selection_img:
    - Description|contains: 7-Zip
    - Image|endswith:
        - \7z.exe
        - \7zr.exe
        - \7za.exe
    - OriginalFileName:
        - 7z.exe
        - 7za.exe
        - 7zr.exe
  selection_extension:
    CommandLine|contains:
      - .dmp
      - .dump
      - .hdmp
  condition: all of selection_*
falsepositives:
  - Legitimate use of 7z with a command line in which ".dmp" or ".dump" appears accidentally
  - Legitimate use of 7z to compress WER ".dmp" files for troubleshooting
level: medium
license: DRL-1.1