detection.wiki

Detection rules › Sigma

VSS backup deletion (WMI)

Status
experimental
Severity
high
Log source
product windows, category process_creation
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker attempts to delete existing VSS backup.

MITRE ATT&CK coverage

TacticTechniques
ImpactT1490 Inhibit System Recovery

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation
Security-AuditingEvent ID 4688A new process has been created.

Rule body yaml

title: VSS backup deletion (WMI)
description: Detects scenarios where an attacker attempts to delete existing VSS backup.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0040-Impact/T1490-Inhibit%20System%20Recovery
- https://www.picussecurity.com/resource/blog/how-to-beat-nefilim-ransomware-attacks
- https://www.itechtics.com/volume-shadow-copies/
- https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/wbadmin
- https://www.picussecurity.com/resource/blog/technique-to-delete-volume-shadow-copies-deviceiocontrol
- https://lolbas-project.github.io/lolbas/Binaries/Wmic/
- https://www.mandiant.com/resources/chasing-avaddon-ransomware
- https://blogs.vmware.com/security/2022/09/threat-report-illuminating-volume-shadow-deletion.html
tags:
- attack.impact
- attack.t1490
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  category: process_creation
detection:
  selection: # wmic shadowcopy delete /nointeractive
    NewProcessName|endswith: \wmic.exe
    CommandLine|contains|all:
      - shadowcopy
      - delete
  condition: selection
falsepositives:
- administrator cleaning outdated backup
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  NewProcessName|endswith: \wmic.exe
  CommandLine|contains|all:
    - shadowcopy
    - delete

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • delete corpus 23 (sigma 16, splunk 6, kusto 1)
  • shadowcopy corpus 6 (sigma 3, splunk 3)
NewProcessNameends_with
  • \wmic.exe corpus 60 (sigma 60)