Detection rules › Kusto
TI map IP entity to AWSCloudTrail
Identifies a match in AWSCloudTrail from any IP IOC from TI
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control | T1071 Application Layer Protocol |
Rule body kusto
id: 69f55be4-1b13-42d0-b975-a1e59c996dd2
name: TI map IP entity to AWSCloudTrail
description: |
Identifies a match in AWSCloudTrail from any IP IOC from TI
severity: Medium
requiredDataConnectors:
- connectorId: ThreatIntelligence
dataTypes:
- ThreatIntelIndicators
- connectorId: ThreatIntelligenceTaxii
dataTypes:
- ThreatIntelIndicators
- connectorId: AWS
dataTypes:
- AWSCloudTrail
- connectorId: MicrosoftDefenderThreatIntelligence
dataTypes:
- ThreatIntelIndicators
queryFrequency: 1h
queryPeriod: 14d
triggerOperator: gt
triggerThreshold: 0
tactics:
- CommandAndControl
relevantTechniques:
- T1071
query: |
let dt_lookBack = 1h; // Look back 1 hour for AWSCloudTrail logs
let ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators
// Fetch threat intelligence indicators related to IP addresses
let IP_Indicators = ThreatIntelIndicators
//extract key part of kv pair
| extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
| where IndicatorType in ("ipv4-addr", "ipv6-addr", "network-traffic")
| extend NetworkSourceIP = toupper(ObservableValue)
| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
// Filter out indicators without relevant IP address fields
| where TimeGenerated >= ago(ioc_lookBack)
// Select the IP entity based on availability of different IP fields
| extend TI_ipEntity = iff(isnotempty(NetworkSourceIP), NetworkSourceIP, NetworkSourceIP)
| extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
| extend Url = iff(ObservableKey == "url:value", ObservableValue, "")
// Exclude local addresses using the ipv4_is_private operator and filtering out specific address prefixes
| where ipv4_is_private(TI_ipEntity) == false and TI_ipEntity !startswith "fe80" and TI_ipEntity !startswith "::" and TI_ipEntity !startswith "127."
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
| where IsActive and (ValidUntil > now() or isempty(ValidUntil));
// Perform a join between IP indicators and AWSCloudTrail logs to identify potential malicious activity
IP_Indicators
| project-reorder *, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, TI_ipEntity
// Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation
| join kind=innerunique (
AWSCloudTrail
| where TimeGenerated >= ago(dt_lookBack)
| extend AWSCloudTrail_TimeGenerated = TimeGenerated // Rename time column for clarity
)
on $left.TI_ipEntity == $right.SourceIpAddress
// Filter out logs that occurred after the expiration of the corresponding indicator
| where AWSCloudTrail_TimeGenerated < ValidUntil
// Group the results by IndicatorId and SourceIpAddress, and keep the log entry with the latest timestamp
| summarize AWSCloudTrail_TimeGenerated = arg_max(AWSCloudTrail_TimeGenerated, *) by Id, SourceIpAddress
// Select the desired output fields
| extend Description = tostring(parse_json(Data).description)
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
| project AWSCloudTrail_TimeGenerated, Description, ActivityGroupNames, Id, ValidUntil, Confidence,
TI_ipEntity, EventName, EventTypeName, UserIdentityAccountId, UserIdentityPrincipalid, UserIdentityUserName, SourceIpAddress,
NetworkSourceIP, Url
// Rename the timestamp field
| extend timestamp = AWSCloudTrail_TimeGenerated
entityMappings:
- entityType: Account
fieldMappings:
- identifier: ObjectGuid
columnName: UserIdentityUserName
- entityType: IP
fieldMappings:
- identifier: Address
columnName: SourceIpAddress
- entityType: URL
fieldMappings:
- identifier: Url
columnName: Url
version: 1.4.6
kind: Scheduled
Stages and Predicates
Parameters
let dt_lookBack = 1h;
let ioc_lookBack = 14d;
The stages below define let IP_Indicators (the rule's main pipeline source).
Stage 1: source
ThreatIntelIndicators
Stage 2: extend
| extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
Stage 3: where
| where IndicatorType in ("ipv4-addr", "ipv6-addr", "network-traffic")
Stage 4: extend
| extend NetworkSourceIP = toupper(ObservableValue)
Stage 5: extend
| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
Stage 6: where
| where TimeGenerated >= ago(ioc_lookBack)
Stage 7: extend (3 consecutive steps)
| extend TI_ipEntity = iff(isnotempty(NetworkSourceIP), NetworkSourceIP, NetworkSourceIP)
| extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
| extend Url = iff(ObservableKey == "url:value", ObservableValue, "")
TI_ipEntity =isnotempty(NetworkSourceIP)NetworkSourceIPNetworkSourceIPStage 8: where
| where ipv4_is_private(TI_ipEntity) == false and TI_ipEntity !startswith "fe80" and TI_ipEntity !startswith "::" and TI_ipEntity !startswith "127."
Stage 9: summarize
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
Stage 10: where
| where IsActive and (ValidUntil > now() or isempty(ValidUntil))
The stages below run on IP_Indicators (the outer pipeline).
Stage 11: project-reorder
IP_Indicators
| project-reorder *, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, TI_ipEntity
Stage 12: join
| join kind=innerunique (
AWSCloudTrail
| where TimeGenerated >= ago(dt_lookBack)
| extend AWSCloudTrail_TimeGenerated = TimeGenerated
)
on $left.TI_ipEntity == $right.SourceIpAddress
Stage 13: where
| where AWSCloudTrail_TimeGenerated < ValidUntil
Stage 14: summarize
| summarize AWSCloudTrail_TimeGenerated = arg_max(AWSCloudTrail_TimeGenerated, *) by Id, SourceIpAddress
Stage 15: extend
| extend Description = tostring(parse_json(Data).description)
Stage 16: extend
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
Stage 17: project
| project AWSCloudTrail_TimeGenerated, Description, ActivityGroupNames, Id, ValidUntil, Confidence,
TI_ipEntity, EventName, EventTypeName, UserIdentityAccountId, UserIdentityPrincipalid, UserIdentityUserName, SourceIpAddress,
NetworkSourceIP, Url
Stage 18: extend
| extend timestamp = AWSCloudTrail_TimeGenerated
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
TI_ipEntity | cidr_match | 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, 169.254.0.0/16, 127.0.0.0/8 |
TI_ipEntity | starts_with | 127. |
TI_ipEntity | starts_with | :: |
TI_ipEntity | starts_with | fe80 |
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 |
|---|---|---|
AWSCloudTrail_TimeGenerated | lt |
|
IndicatorType | 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 |
|---|---|
AWSCloudTrail_TimeGenerated | project |
ActivityGroupNames | project |
Confidence | project |
Description | project |
EventName | project |
EventTypeName | project |
Id | project |
NetworkSourceIP | project |
SourceIpAddress | project |
TI_ipEntity | project |
Url | project |
UserIdentityAccountId | project |
UserIdentityPrincipalid | project |
UserIdentityUserName | project |
ValidUntil | project |
timestamp | extend |