CVE-2021-31979 CVE-2021-33771 Exploits


Description

Detects patterns as noticed in exploitation of Windows CVE-2021-31979 CVE-2021-33771 vulnerability and DevilsTongue malware by threat group Sourgum

Query · sigma

selection:
  TargetObject|endswith:
  - CLSID\{CF4CC405-E2C5-4DDD-B3CE-5E7582D8C9FA}\InprocServer32\(Default)
  - CLSID\{7C857801-7381-11CF-884D-00AA004B2E24}\InProcServer32\(Default)
filter:
  Details|endswith:
  - system32\wbem\wmiutils.dll
  - system32\wbem\wbemsvc.dll
condition: selection and not filter

Known false positives

  • Unlikely
Raw source CVE-2021-31979 CVE-2021-33771 Exploits · Sigma
Esc
Published by SigmaHQ/sigma ↗, licensed under Detection Rule License 1.1 ↗. Reproduced here unmodified.
title: CVE-2021-31979 CVE-2021-33771 Exploits
id: 32b5db62-cb5f-4266-9639-0fa48376ac00
status: test
description: Detects patterns as noticed in exploitation of Windows CVE-2021-31979 CVE-2021-33771 vulnerability and DevilsTongue malware by threat group Sourgum
references:
    - https://www.microsoft.com/security/blog/2021/07/15/protecting-customers-from-a-private-sector-offensive-actor-using-0-day-exploits-and-devilstongue-malware/
    - https://citizenlab.ca/2021/07/hooking-candiru-another-mercenary-spyware-vendor-comes-into-focus/
author: Sittikorn S, frack113
date: 2021-07-16
modified: 2023-08-17
tags:
    - attack.initial-access
    - attack.execution
    - attack.credential-access
    - attack.t1566
    - attack.t1203
    - cve.2021-33771
    - cve.2021-31979
    - detection.emerging-threats
    # - threat_group.Sourgum
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|endswith:
            - CLSID\{CF4CC405-E2C5-4DDD-B3CE-5E7582D8C9FA}\InprocServer32\(Default)
            - CLSID\{7C857801-7381-11CF-884D-00AA004B2E24}\InProcServer32\(Default)
    filter:
        Details|endswith:
            - system32\wbem\wmiutils.dll
            - system32\wbem\wbemsvc.dll
    condition: selection and not filter
falsepositives:
    - Unlikely
level: critical

Detection rules belong to the projects that publish them and remain under their own licenses. This site indexes and links to them; it claims no rights in them.