Azure Full Network Packet Capture Detected

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Identifies potential full network packet capture in Azure. Packet Capture is an Azure Network Watcher feature that can be used to inspect network traffic. This feature can potentially be abused to read sensitive data from unencrypted internal traffic.

Rule type: query

Rule indices:

  • filebeat-*
  • logs-azure*

Severity: medium

Risk score: 47

Runs every: 5 minutes

Searches indices from: now-25m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Cloud
  • Azure
  • Continuous Monitoring
  • SecOps
  • Monitoring

Version: 1

Added (Elastic Stack release): 7.16.0

Rule authors: Austin Songer

Rule license: Elastic License v2

Potential false positives

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Full Network Packet Capture may be done by a system or network administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment. Full Network Packet Capture from unfamiliar users or hosts should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

Investigation guide

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## Config

The Azure Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.

Rule query

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event.dataset:azure.activitylogs and
azure.activitylogs.operation_name: (
"MICROSOFT.NETWORK/*/STARTPACKETCAPTURE/ACTION" or
"MICROSOFT.NETWORK/*/VPNCONNECTIONS/STARTPACKETCAPTURE/ACTION" or
"MICROSOFT.NETWORK/*/PACKETCAPTURES/WRITE" ) and
event.outcome:(Success or success)

Threat mapping

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Framework: MITRE ATT&CKTM