Monitor AWS Credential abuse or hijacking
| Id | 32555639-b639-4c2b-afda-c0ae0abefa55 |
| Rulename | Monitor AWS Credential abuse or hijacking |
| Description | Looking for GetCallerIdentity Events where the UserID Type is AssumedRole An attacker who has assumed the role of a legitimate account can call the GetCallerIdentity function to determine what account they are using. A legitimate user using legitimate credentials would not need to call GetCallerIdentity since they should already know what account they are using. More Information: https://duo.com/decipher/trailblazer-hunts-compromised-credentials-in-aws AWS STS GetCallerIdentity API: https://docs.aws.amazon.com/STS/latest/APIReference/API_GetCallerIdentity.html |
| Severity | Low |
| Tactics | Discovery |
| Techniques | T1087 |
| Required data connectors | AWS AWSS3 |
| Kind | Scheduled |
| Query frequency | 1d |
| Query period | 1d |
| Trigger threshold | 0 |
| Trigger operator | gt |
| Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_CredentialHijack.yaml |
| Version | 1.0.3 |
| Arm template | 32555639-b639-4c2b-afda-c0ae0abefa55.json |
AWSCloudTrail
| where EventName =~ "GetCallerIdentity" and UserIdentityType =~ "AssumedRole"
| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
| extend UserName = tostring(split(UserIdentityArn, '/')[-1])
| extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
| extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by SourceIpAddress, EventName, EventTypeName, UserIdentityType, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, UserIdentityPrincipalid,
UserAgent, UserIdentityUserName, SessionMfaAuthenticated,AWSRegion, EventSource, AdditionalEventData, ResponseElements
| extend timestamp = StartTime
| sort by EndTime desc nulls last
entityMappings:
- entityType: Account
fieldMappings:
- columnName: AccountName
identifier: Name
- columnName: AccountUPNSuffix
identifier: UPNSuffix
- columnName: RecipientAccountId
identifier: CloudAppAccountId
- entityType: IP
fieldMappings:
- columnName: SourceIpAddress
identifier: Address
requiredDataConnectors:
- dataTypes:
- AWSCloudTrail
connectorId: AWS
- dataTypes:
- AWSCloudTrail
connectorId: AWSS3
queryPeriod: 1d
query: |
AWSCloudTrail
| where EventName =~ "GetCallerIdentity" and UserIdentityType =~ "AssumedRole"
| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
| extend UserName = tostring(split(UserIdentityArn, '/')[-1])
| extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
| extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by SourceIpAddress, EventName, EventTypeName, UserIdentityType, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, UserIdentityPrincipalid,
UserAgent, UserIdentityUserName, SessionMfaAuthenticated,AWSRegion, EventSource, AdditionalEventData, ResponseElements
| extend timestamp = StartTime
| sort by EndTime desc nulls last
description: |
'Looking for GetCallerIdentity Events where the UserID Type is AssumedRole
An attacker who has assumed the role of a legitimate account can call the GetCallerIdentity function to determine what account they are using.
A legitimate user using legitimate credentials would not need to call GetCallerIdentity since they should already know what account they are using.
More Information: https://duo.com/decipher/trailblazer-hunts-compromised-credentials-in-aws
AWS STS GetCallerIdentity API: https://docs.aws.amazon.com/STS/latest/APIReference/API_GetCallerIdentity.html '
version: 1.0.3
name: Monitor AWS Credential abuse or hijacking
relevantTechniques:
- T1087
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_CredentialHijack.yaml
kind: Scheduled
status: Available
queryFrequency: 1d
severity: Low
tactics:
- Discovery
triggerOperator: gt
id: 32555639-b639-4c2b-afda-c0ae0abefa55
triggerThreshold: 0
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"apiVersion": "2023-02-01-preview",
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/32555639-b639-4c2b-afda-c0ae0abefa55')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/32555639-b639-4c2b-afda-c0ae0abefa55')]",
"properties": {
"alertRuleTemplateName": "32555639-b639-4c2b-afda-c0ae0abefa55",
"customDetails": null,
"description": "'Looking for GetCallerIdentity Events where the UserID Type is AssumedRole\nAn attacker who has assumed the role of a legitimate account can call the GetCallerIdentity function to determine what account they are using.\nA legitimate user using legitimate credentials would not need to call GetCallerIdentity since they should already know what account they are using.\nMore Information: https://duo.com/decipher/trailblazer-hunts-compromised-credentials-in-aws \nAWS STS GetCallerIdentity API: https://docs.aws.amazon.com/STS/latest/APIReference/API_GetCallerIdentity.html '\n",
"displayName": "Monitor AWS Credential abuse or hijacking",
"enabled": true,
"entityMappings": [
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "AccountName",
"identifier": "Name"
},
{
"columnName": "AccountUPNSuffix",
"identifier": "UPNSuffix"
},
{
"columnName": "RecipientAccountId",
"identifier": "CloudAppAccountId"
}
]
},
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "SourceIpAddress",
"identifier": "Address"
}
]
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_CredentialHijack.yaml",
"query": "AWSCloudTrail\n| where EventName =~ \"GetCallerIdentity\" and UserIdentityType =~ \"AssumedRole\"\n| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)\n| extend UserName = tostring(split(UserIdentityArn, '/')[-1])\n| extend AccountName = case( UserIdentityPrincipalid == \"Anonymous\", \"Anonymous\", isempty(UserIdentityUserName), UserName, UserIdentityUserName)\n| extend AccountName = iif(AccountName contains \"@\", tostring(split(AccountName, '@', 0)[0]), AccountName),\n AccountUPNSuffix = iif(AccountName contains \"@\", tostring(split(AccountName, '@', 1)[0]), \"\")\n| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by SourceIpAddress, EventName, EventTypeName, UserIdentityType, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, UserIdentityPrincipalid,\nUserAgent, UserIdentityUserName, SessionMfaAuthenticated,AWSRegion, EventSource, AdditionalEventData, ResponseElements\n| extend timestamp = StartTime\n| sort by EndTime desc nulls last\n",
"queryFrequency": "P1D",
"queryPeriod": "P1D",
"severity": "Low",
"status": "Available",
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Discovery"
],
"techniques": [
"T1087"
],
"templateVersion": "1.0.3",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}