:warning: THIS IS A EXPERIMENTAL DETECTION

This detection has been marked experimental by the Splunk Threat Research team. This means we have not been able to test, simulate, or build datasets for this detection. Use at your own risk. This analytic is NOT supported.

Try in Splunk Security Cloud

Description

This search detects SIGRed via Splunk Stream.

  • Type: TTP

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2020-07-28
  • Author: Shannon Davis, Splunk
  • ID: babd8d10-d073-11ea-87d0-0242ac130003

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1203 Exploitation for Client Execution Execution
Kill Chain Phase
  • Installation
NIST
  • DE.CM
CIS20
  • CIS 13
CVE
ID Summary CVSS
CVE-2020-1350 A remote code execution vulnerability exists in Windows Domain Name System servers when they fail to properly handle requests, aka 'Windows DNS Server Remote Code Execution Vulnerability'. 10.0 


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`stream_dns` 
| spath "query_type{}" 
| search "query_type{}" IN (SIG,KEY) 
| spath protocol_stack 
| search protocol_stack="ip:tcp:dns" 
| append [search `stream_tcp` bytes_out>65000] 
| `detect_windows_dns_sigred_via_splunk_stream_filter` 
| stats count by flow_id 
| where count>1 
| fields - count

Macros

The SPL above uses the following Macros:

:information_source: detect_windows_dns_sigred_via_splunk_stream_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time

How To Implement

You must be ingesting Splunk Stream DNS and Splunk Stream TCP. We are detecting SIG and KEY records via stream:dns and TCP payload over 65KB in size via stream:tcp. Replace the macro definitions ('stream:dns' and 'stream:tcp') with configurations for your Splunk environment.

Known False Positives

unknown

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
25.0 50 50 tbd

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

source | version: 1