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Tailscale: MagicDNS disabled

Description

Identifies when MagicDNS is turned off on the tailnet. Disabling MagicDNS changes DNS behaviour for every device and is occasionally a precursor to wider DNS hijacking - verify the change was intentional.
Rule type
Scheduled
Version
1.0.0
Declared status
Available
Query frequency
15m
Query period
15m
Trigger
gt 0

Declared MITRE coverage

Declared sources

Metadata from the source file. No dependencies inferred from KQL.

Connectors

Data types

KQL query

Original query, unchanged.

Tailscale_Audit_CL
| where Action == "UPDATE"
| where tostring(Target.type) == "TAILNET"
| where tostring(Target.property) == "MAGICDNS_PREFERENCES"
| extend ActorLogin = tostring(Actor.loginName)
| extend OldMagicDns = tobool(Old.magicDNS)
| extend NewMagicDns = tobool(New.magicDNS)
| where OldMagicDns == true and NewMagicDns == false
| project TimeGenerated, ActorLogin, OldMagicDns, NewMagicDns, Origin

Declared entities

Account

Related content

Links established from declared identifiers and solution manifests.

Source provenance

GitHub

Displayed values come from files in Azure/Azure-Sentinel. They describe the published template, not your workspace configuration.

Source identifier
f8a9b0c1-4567-8901-23ab-cdef12345020
Additional source files 2Solutions/Tailscale (CCF)/Analytic Rules/TailscaleMagicDnsDisabled.yamlsource ↗Solutions/Tailscale (CCF)/Data/Solution_Tailscale.jsonsolution-membership ↗
GSTEP / CATALOG TRACKING

Added to catalog : 16 Sept 2026 · 05:49 UTC
Last change observed : 16 Sept 2026 · 05:49 UTC

GSTEP sync dates, separate from the source content’s publication dates.