Detection rules › Sigma

ADS Zone.Identifier Deleted By Uncommon Application

Status
test
Severity
medium
Log source
category file_delete, product windows
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the deletion of the "Zone.Identifier" ADS by an uncommon process. Attackers can leverage this in order to bypass security restrictions that make use of the ADS such as Microsoft Office apps.

Known false positives

  • Other third party applications not listed.

MITRE ATT&CK coverage

Telemetry coverage

Rule body

title: ADS Zone.Identifier Deleted By Uncommon Application
id: 3109530e-ab47-4cc6-a953-cac5ebcc93ae
related:
    - id: 7eac0a16-5832-4e81-865f-0268a6d19e4b
      type: similar
status: test
description: Detects the deletion of the "Zone.Identifier" ADS by an uncommon process. Attackers can leverage this in order to bypass security restrictions that make use of the ADS such as Microsoft Office apps.
references:
    - https://securityliterate.com/how-malware-abuses-the-zone-identifier-to-circumvent-detection-and-analysis/
    - Internal Research
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-09-04
modified: 2025-07-04
tags:
    - attack.stealth
    - attack.t1070.004
logsource:
    product: windows
    category: file_delete
detection:
    selection:
        TargetFilename|endswith: ':Zone.Identifier'
    filter_main_generic:
        # Note: in some envs this activity might be performed by other software. Apply additional filters as necessary
        Image:
            - 'C:\Program Files\PowerShell\7-preview\pwsh.exe'
            - 'C:\Program Files\PowerShell\7\pwsh.exe'
            - 'C:\Windows\explorer.exe'
            - 'C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe'
            - 'C:\Windows\SysWOW64\explorer.exe'
            - 'C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe'
    filter_optional_browsers_chrome:
        Image:
            - 'C:\Program Files (x86)\Google\Chrome\Application\chrome.exe'
            - 'C:\Program Files\Google\Chrome\Application\chrome.exe'
    filter_optional_browsers_firefox:
        Image:
            - 'C:\Program Files (x86)\Mozilla Firefox\firefox.exe'
            - 'C:\Program Files\Mozilla Firefox\firefox.exe'
    filter_optional_browsers_msedge:
        Image:
            - 'C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe'
            - 'C:\Program Files\Microsoft\Edge\Application\msedge.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Other third party applications not listed.
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_* and not 1 of filter_optional_*

Stage 1: selection

selection:
    TargetFilename|endswith: ':Zone.Identifier'

Stage 2: not filter_main_generic

filter_main_generic:
    Image:
        - 'C:\Program Files\PowerShell\7-preview\pwsh.exe'
        - 'C:\Program Files\PowerShell\7\pwsh.exe'
        - 'C:\Windows\explorer.exe'
        - 'C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe'
        - 'C:\Windows\SysWOW64\explorer.exe'
        - 'C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe'

Stage 3: not filter_optional_*

filter_optional_browsers_chrome:
    Image:
        - 'C:\Program Files (x86)\Google\Chrome\Application\chrome.exe'
        - 'C:\Program Files\Google\Chrome\Application\chrome.exe'
filter_optional_browsers_firefox:
    Image:
        - 'C:\Program Files (x86)\Mozilla Firefox\firefox.exe'
        - 'C:\Program Files\Mozilla Firefox\firefox.exe'
filter_optional_browsers_msedge:
    Image:
        - 'C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe'
        - 'C:\Program Files\Microsoft\Edge\Application\msedge.exe'

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
ImageeqC:\Program Files\PowerShell\7-preview\pwsh.exeexcludes:Image field:"Image" value:"C:\Program Files\PowerShell\7-preview\pwsh.exe"
ImageeqC:\Program Files\PowerShell\7\pwsh.exeexcludes:Image field:"Image" value:"C:\Program Files\PowerShell\7\pwsh.exe"
ImageeqC:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exeexcludes:Image field:"Image" value:"C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe"
ImageeqC:\Windows\SysWOW64\explorer.exeexcludes:Image field:"Image" value:"C:\Windows\SysWOW64\explorer.exe"
ImageeqC:\Windows\System32\WindowsPowerShell\v1.0\powershell.exeexcludes:Image field:"Image" value:"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe"
ImageeqC:\Windows\explorer.exeexcludes:Image field:"Image" value:"C:\Windows\explorer.exe"
ImageeqC:\Program Files (x86)\Google\Chrome\Application\chrome.exeexcludes:Image field:"Image" value:"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe"
ImageeqC:\Program Files (x86)\Microsoft\Edge\Application\msedge.exeexcludes:Image field:"Image" value:"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe"
ImageeqC:\Program Files (x86)\Mozilla Firefox\firefox.exeexcludes:Image field:"Image" value:"C:\Program Files (x86)\Mozilla Firefox\firefox.exe"
ImageeqC:\Program Files\Google\Chrome\Application\chrome.exeexcludes:Image field:"Image" value:"C:\Program Files\Google\Chrome\Application\chrome.exe"
ImageeqC:\Program Files\Microsoft\Edge\Application\msedge.exeexcludes:Image field:"Image" value:"C:\Program Files\Microsoft\Edge\Application\msedge.exe"
ImageeqC:\Program Files\Mozilla Firefox\firefox.exeexcludes:Image field:"Image" value:"C:\Program Files\Mozilla Firefox\firefox.exe"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenameends_with
  • :Zone.Identifier corpus 6 (sigma 4, splunk 2)
field:"TargetFilename" kind:ends_with value:":Zone.Identifier"