: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

Adversaries may leverage traffic mirroring in order to automate data exfiltration over compromised network infrastructure. Traffic mirroring is a native feature for some network devices and used for network analysis and may be configured to duplicate traffic and forward to one or more destinations for analysis by a network analyzer or other monitoring device.

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

  • Last Updated: 2020-10-28
  • Author: Mikael Bjerkeland, Splunk
  • ID: 42b3b753-5925-49c5-9742-36fa40a73990

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1200 Hardware Additions Initial Access
T1020 Automated Exfiltration Exfiltration
T1498 Network Denial of Service Impact
T1020.001 Traffic Duplication Exfiltration
Kill Chain Phase
  • Delivery
  • Actions on Objectives
NIST
  • ID.AM
  • PR.DS
CIS20
  • CIS 1
  • CIS 11
CVE
1
2
3
4
5
`cisco_networks` (facility="MIRROR" mnemonic="ETH_SPAN_SESSION_UP") OR (facility="SPAN" mnemonic="SESSION_UP") OR (facility="SPAN" mnemonic="PKTCAP_START") OR (mnemonic="CFGLOG_LOGGEDCMD" command="monitor session*") 
| stats min(_time) AS firstTime max(_time) AS lastTime count BY host facility mnemonic 
| `security_content_ctime(firstTime)`
|`security_content_ctime(lastTime)` 
| `detect_traffic_mirroring_filter`

Macros

The SPL above uses the following Macros:

:information_source: detect_traffic_mirroring_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
  • facility
  • mnemonic
  • host

How To Implement

This search uses a standard SPL query on logs from Cisco Network devices. The network devices must log with a severity level of minimum "5 - notification". The search also requires that the Cisco Networks Add-on for Splunk (https://splunkbase.splunk.com/app/1467) is used to parse the logs from the Cisco network devices and that the devices have been configured according to the documentation of the Cisco Networks Add-on. Also note that an attacker may disable logging from the device prior to enabling traffic mirroring.

Known False Positives

This search will return false positives for any legitimate traffic captures by network administrators.

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