DNS Server Discovery Via LDAP Query — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: low. Source dates: 2022-08-20 / 2023-09-18.

{
  "product": "windows",
  "category": "dns_query"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: ac4c207dbcfbd2b449d7397256cd4a279f1da27fa2e85cd6192c8f841eefb68e

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: DNS Server Discovery Via LDAP Query
id: a21bcd7e-38ec-49ad-b69a-9ea17e69509e
status: test
description: Detects DNS server discovery via LDAP query requests from uncommon applications
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/980f3f83fd81f37c1ca9c02dccfd1c3d9f9d0841/atomics/T1016/T1016.md#atomic-test-9---dns-server-discovery-using-nslookup
    - https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-adts/7fcdce70-5205-44d6-9c3a-260e616a2f04
author: frack113
date: 2022-08-20
modified: 2023-09-18
tags:
    - attack.discovery
    - attack.t1482
logsource:
    product: windows
    category: dns_query
detection:
    selection:
        QueryName|startswith: '_ldap.'
    filter_main_generic:
        Image|contains:
            - ':\Program Files\'
            - ':\Program Files (x86)\'
            - ':\Windows\'
    filter_main_defender:
        Image|contains: ':\ProgramData\Microsoft\Windows Defender\Platform\'
        Image|endswith: '\MsMpEng.exe'
    filter_main_unknown:
        Image: '<unknown process>'
    filter_optional_azure:
        Image|startswith: 'C:\WindowsAzure\GuestAgent'
    filter_main_null:
        Image: null
    filter_optional_browsers:
        # Note: This list is for browsers installed in the user context. To avoid basic evasions based on image name. Best to baseline this list with the browsers you use internally and add their full paths.
        Image|endswith:
            - '\chrome.exe'
            - '\firefox.exe'
            - '\opera.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Likely
# Note: Incrase the level once a baseline is established
level: low

Original YAML and metadata in JSON

False positives

• Likely

Source references

• https://github.com/redcanaryco/atomic-red-team/blob/980f3f83fd81f37c1ca9c02dccfd1c3d9f9d0841/atomics/T1016/T1016.md#atomic-test-9---dns-server-discovery-using-nslookup
• https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-adts/7fcdce70-5205-44d6-9c3a-260e616a2f04