↳ GitHub sourceAnalytics ruleHigh
Network Port Sweep from External Network (ASIM Network Session schema)
Description
'This detection rule detects scenarios when a particular port is being scanned by multiple external sources. The rule utilize [ASIM](https://aka.ms/AboutASIM) normalization, and is applied to any source which supports the ASIM Network Session schema.'
- Rule type
- Scheduled
- Version
- 1.0.5
- 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.
let lookback = 1h;
let threshold = 20;
_Im_NetworkSession(starttime=ago(lookback),endtime=now())
| where NetworkDirection == "Inbound"
| summarize make_set(DstIpAddr,100) by SrcIpAddr, DstPortNumber
| where array_length(set_DstIpAddr) > threshold
Related content
Links established from declared identifiers and solution manifests.
Source provenance
GitHubDisplayed values come from files in Azure/Azure-Sentinel. They describe the published template, not your workspace configuration.
- Commit
9800e51↗- Source identifier
cd8faa84-4464-4b4e-96dc-b22f50c27541
GSTEP / CATALOG TRACKING
Added to catalog : 16 Sept 2026 · 05:49 UTC
Last change observed : 16 Sept 2026 · 05:49 UTC