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Cisco SEG - Suspicious sender domain

Description

'Detects suspicious sender domain age.'
Rule type
Scheduled
Version
1.0.3
Declared status
Available
Query frequency
1h
Query period
1h
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.

CiscoSEGEvent
| where NetworkDirection =~ 'Incoming'
| extend rec_domain = extract(@'@(.*)', 1, DstUserName)
| extend s_domain = extract(@'@(.*)', 1, SrcUserName)
| where s_domain != rec_domain
| where tostring(AdditionalFields) has 'ESASDRDomainAge'
| extend domain_age = extract(@'ESASDRDomainAge":"(.*days)"', 1, tostring(AdditionalFields))
| extend yy = toint(extract(@'(\d+)\syears', 1, domain_age))
| extend mm = toint(extract(@'(\d+)\smonths', 1, domain_age))
| extend dd = toint(extract(@'(\d+)\sdays', 1, domain_age))
| where isempty(yy)
| where isempty(mm) or mm <= 2
| extend AccountCustomEntity = SrcUserName

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
ef0a253c-95b5-48e1-8ebc-dbeb073b9338
Additional source files 2Solutions/CiscoSEG/Analytic Rules/CiscoSEGSuspiciousSenderDomain.yamlsource ↗Solutions/CiscoSEG/Data/Solution_CiscoSEG.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.