Elastic Security Detection Rules

ESXi Firewall Disabled

Last updated 2 days ago on 2026-09-30
Created 2 days ago on 2026-09-30

About

Detects the ESXi firewall being turned off or switched to a default allow. The firewall is the host filter for management services. Disabling it, or setting the default action to accept, lets later connections reach services that were previously blocked.
Tags
Domain: EndpointData Source: VMware vSphereUse Case: Threat DetectionTactic: Defense EvasionRule Type: Custom Query (KQL)Platform: VMware ESXiLanguage: kuery
Severity
high
Risk Score
73
MITRE ATT&CK™

Defense Evasion (TA0005)(external, opens in a new tab or window)

↳ Impair Defenses (T1562)(external, opens in a new tab or window)

False Positive Examples
Firewall changes are part of some network troubleshooting and product installs. Confirm the change was temporary and that `--enabled true` and a DROP default action were restored.
License
Elastic License v2(external, opens in a new tab or window)

Definition

Rule Type
Query (Kibana Query Language)
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-vsphere.log-*
Related Integrations

vsphere(external, opens in a new tab or window)

Query
text code block:
data_stream.dataset:vsphere.log and message:("Firewall has been disabled" or "network firewall set" and ("--default-action true" or "--default-action=true" or "--enabled false" or "--enabled=false"))

Install detection rules in Elastic Security

Detect ESXi Firewall Disabled in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).