Detection rules › Kusto
TI Map URL Entity to DeviceNetworkEvents
'This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in DeviceNetworkEvents.'
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control | T1071 Application Layer Protocol |
Rule body kusto
id: 4f0356b2-d344-4c19-9375-31b9575d80cb
name: TI Map URL Entity to DeviceNetworkEvents
description: |
'This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in DeviceNetworkEvents.'
severity: Medium
requiredDataConnectors:
- connectorId: MicrosoftThreatProtection
dataTypes:
- DeviceNetworkEvents
- connectorId: ThreatIntelligence
dataTypes:
- ThreatIntelIndicators
- connectorId: ThreatIntelligenceTaxii
dataTypes:
- ThreatIntelIndicators
- connectorId: MicrosoftDefenderThreatIntelligence
dataTypes:
- ThreatIntelIndicators
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
- CommandAndControl
relevantTechniques:
- T1071
query: |
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let DeviceNetworkEvents_ = DeviceNetworkEvents
| where TimeGenerated >= ago(dt_lookBack)
| where ActionType !has "ConnectionFailed"
| project-rename DeviceNetworkEvents_TimeGenerated = TimeGenerated;
let DeviceNetworkEventUrls = DeviceNetworkEvents_
| distinct Url = RemoteUrl
| summarize make_list(Url);
ThreatIntelIndicators
//extract key part of kv pair
| extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
| where IndicatorType == "url"
| extend Url = ObservableValue
| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
| where TimeGenerated >= ago(ioc_lookBack)
| extend Url = tolower(Url)
| where Url in (DeviceNetworkEventUrls)
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
| where IsActive and (ValidUntil > now() or isempty(ValidUntil))
| extend Description = tostring(parse_json(Data).description)
| where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
| project-reorder *, Tags, TrafficLightProtocolLevel, Url, Type
| join kind=innerunique (DeviceNetworkEvents_) on $left.Url == $right.RemoteUrl
| where DeviceNetworkEvents_TimeGenerated < ValidUntil
| summarize DeviceNetworkEvents_TimeGenerated = arg_max(DeviceNetworkEvents_TimeGenerated, *) by Id, Url
| extend Description = tostring(parse_json(Data).description)
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
| project DeviceNetworkEvents_TimeGenerated, Id, Url, Confidence, Description, Type, Tags, TrafficLightProtocolLevel, ActionType, DeviceId, DeviceName, InitiatingProcessAccountUpn, InitiatingProcessCommandLine, RemoteIP, RemotePort
| extend Name = tostring(split(InitiatingProcessAccountUpn, '@', 0)[0]), UPNSuffix = tostring(split(InitiatingProcessAccountUpn, '@', 1)[0])
| extend timestamp = DeviceNetworkEvents_TimeGenerated, UserPrincipalName = InitiatingProcessAccountUpn
entityMappings:
- entityType: Account
fieldMappings:
- identifier: Name
columnName: Name
- identifier: UPNSuffix
columnName: UPNSuffix
- entityType: Host
fieldMappings:
- identifier: FullName
columnName: DeviceName
- entityType: URL
fieldMappings:
- identifier: Url
columnName: Url
- entityType: Process
fieldMappings:
- identifier: CommandLine
columnName: InitiatingProcessCommandLine
version: 1.0.5
kind: Scheduled
Stages and Predicates
Parameters
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
Let binding: DeviceNetworkEvents_
let DeviceNetworkEvents_ = DeviceNetworkEvents
| where TimeGenerated >= ago(dt_lookBack)
| where ActionType !has "ConnectionFailed"
| project-rename DeviceNetworkEvents_TimeGenerated = TimeGenerated;
Derived from dt_lookBack.
Let binding: DeviceNetworkEventUrls
let DeviceNetworkEventUrls = DeviceNetworkEvents_
| distinct Url = RemoteUrl
| summarize make_list(Url);
Derived from DeviceNetworkEvents_.
Stage 1: source
ThreatIntelIndicators
Stage 2: extend
| extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
Stage 3: where
| where IndicatorType == "url"
Stage 4: extend
| extend Url = ObservableValue
Stage 5: extend
| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
Stage 6: where
| where TimeGenerated >= ago(ioc_lookBack)
Stage 7: extend
| extend Url = tolower(Url)
Stage 8: where
| where Url in (DeviceNetworkEventUrls)
References DeviceNetworkEventUrls (defined above).
Stage 9: summarize
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
Stage 10: where
| where IsActive and (ValidUntil > now() or isempty(ValidUntil))
Stage 11: extend
| extend Description = tostring(parse_json(Data).description)
Stage 12: where
| where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
Stage 13: project-reorder
| project-reorder *, Tags, TrafficLightProtocolLevel, Url, Type
Stage 14: join
| join kind=innerunique (DeviceNetworkEvents_) on $left.Url == $right.RemoteUrl
Stage 15: where
| where DeviceNetworkEvents_TimeGenerated < ValidUntil
Stage 16: summarize
| summarize DeviceNetworkEvents_TimeGenerated = arg_max(DeviceNetworkEvents_TimeGenerated, *) by Id, Url
Stage 17: extend
| extend Description = tostring(parse_json(Data).description)
Stage 18: extend
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
Stage 19: project
| project DeviceNetworkEvents_TimeGenerated, Id, Url, Confidence, Description, Type, Tags, TrafficLightProtocolLevel, ActionType, DeviceId, DeviceName, InitiatingProcessAccountUpn, InitiatingProcessCommandLine, RemoteIP, RemotePort
Stage 20: extend
| extend Name = tostring(split(InitiatingProcessAccountUpn, '@', 0)[0]), UPNSuffix = tostring(split(InitiatingProcessAccountUpn, '@', 1)[0])
Stage 21: extend
| extend timestamp = DeviceNetworkEvents_TimeGenerated, UserPrincipalName = InitiatingProcessAccountUpn
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
Description | contains | State: falsepos; |
Description | contains | State: inactive; |
ActionType | match | ConnectionFailed |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
DeviceNetworkEvents_TimeGenerated | lt |
|
IndicatorType | eq |
|
Url | in |
|
ValidUntil | is_null |
Output fields
Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.
| Field | Source |
|---|---|
ActionType | project |
Confidence | project |
Description | project |
DeviceId | project |
DeviceName | project |
DeviceNetworkEvents_TimeGenerated | project |
Id | project |
InitiatingProcessAccountUpn | project |
InitiatingProcessCommandLine | project |
RemoteIP | project |
RemotePort | project |
Tags | project |
TrafficLightProtocolLevel | project |
Type | project |
Url | project |
Name | extend |
UPNSuffix | extend |
UserPrincipalName | extend |
timestamp | extend |