Azure Activity Logs: VPN Gateway Connection Modified or Deleted

Alerts on Azure VPN connection updates or removals recorded in Activity Logs.

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azure-activity-logs-vpn-gateway-connection-modified-or-deleted-61171ffc

title: "Azure Activity Logs: VPN Gateway Connection Modified or Deleted"
id: c2f0cffa-1300-4945-971a-545f2d170a60
status: test
description: This rule flags Azure activity log events where a VPN connection on a VPN gateway is modified (WRITE) or removed (DELETE). Such changes can disrupt connectivity or be used to redirect VPN traffic, making it important for detecting unauthorized configuration tampering. It relies on Azure Activity Logs entries with operation names targeting VPNCONNECTIONS WRITE and DELETE under the MICROSOFT.NETWORK/VPNGATEWAYS provider.
references:
  - https://learn.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/activity_logs/azure_vpn_connection_modified_or_deleted.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-08-08
modified: 2022-08-23
tags:
  - attack.impact
logsource:
  product: azure
  service: activitylogs
detection:
  selection:
    operationName:
      - MICROSOFT.NETWORK/VPNGATEWAYS/VPNCONNECTIONS/WRITE
      - MICROSOFT.NETWORK/VPNGATEWAYS/VPNCONNECTIONS/DELETE
  condition: selection
falsepositives:
  - VPN Connection being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
  - VPN Connection modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium
license: DRL-1.1
related:
  - id: 61171ffc-d79c-4ae5-8e10-9323dba19cd3
    type: derived

What it detects

This rule flags Azure activity log events where a VPN connection on a VPN gateway is modified (WRITE) or removed (DELETE). Such changes can disrupt connectivity or be used to redirect VPN traffic, making it important for detecting unauthorized configuration tampering. It relies on Azure Activity Logs entries with operation names targeting VPNCONNECTIONS WRITE and DELETE under the MICROSOFT.NETWORK/VPNGATEWAYS provider.

Known false positives

VPN Connection being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
VPN Connection modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.