AWSCloudTrail - Changes to AWS Security Group ingress and egress settings

let EventNameList = dynamic([ "AuthorizeSecurityGroupEgress", "AuthorizeSecurityGroupIngress", "RevokeSecurityGroupEgress", "RevokeSecurityGroupIngress"]);
AWSCloudTrail
| where EventName in~ (EventNameList)
| 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 EventCount=count(), StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated)
by EventSource, EventName, UserIdentityType, RecipientAccountId, AccountName, AccountUPNSuffix, SourceIpAddress, UserAgent, SessionMfaAuthenticated, AWSRegion,
AdditionalEventData, UserIdentityAccountId, UserIdentityPrincipalid, ResponseElements

name: AWSCloudTrail - Changes to AWS Security Group ingress and egress settings
triggerOperator: gt
query: |
  let EventNameList = dynamic([ "AuthorizeSecurityGroupEgress", "AuthorizeSecurityGroupIngress", "RevokeSecurityGroupEgress", "RevokeSecurityGroupIngress"]);
  AWSCloudTrail
  | where EventName in~ (EventNameList)
  | 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 EventCount=count(), StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated)
  by EventSource, EventName, UserIdentityType, RecipientAccountId, AccountName, AccountUPNSuffix, SourceIpAddress, UserAgent, SessionMfaAuthenticated, AWSRegion,
  AdditionalEventData, UserIdentityAccountId, UserIdentityPrincipalid, ResponseElements
queryFrequency: 1d
description: |
  A Security Group acts as a virtual firewall for an AWS instance to control inbound and outbound traffic. This rule detects AWS CloudTrail events for changes to Security Group ingress and egress settings.
  Investigate to validate the legitimacy of the activity and identify potential malicious activity.
id: 4f19d4e3-ec5f-4abc-9e61-819eb131758c
triggerThreshold: 0
queryPeriod: 1d
version: 1.0.5
kind: Scheduled
customDetails:
  AWSRegion: AWSRegion
  UserIdentityUserName: UserIdentityUserName
  EventName: EventName
  UserIdentityType: UserIdentityType
  UserAgent: UserAgent
  UserIdentityArn: UserIdentityArn
status: Available
severity: Low
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
- connectorId: AWSS3
  dataTypes:
  - AWSCloudTrail
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_IngressEgressSecurityGroupChange.yaml
alertDetailsOverride:
  alertDescriptionFormat: AWS Security Group ingress/egress change activity {{EventName}} was detected for {{AccountName}} from {{SourceIpAddress}}.
  alertDisplayNameFormat: AWS Security Group ingress/egress change by {{AccountName}} from {{SourceIpAddress}}
relevantTechniques:
- T1562.007
tactics:
- DefenseEvasion
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/4f19d4e3-ec5f-4abc-9e61-819eb131758c')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4f19d4e3-ec5f-4abc-9e61-819eb131758c')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "AWS Security Group ingress/egress change activity {{EventName}} was detected for {{AccountName}} from {{SourceIpAddress}}.",
          "alertDisplayNameFormat": "AWS Security Group ingress/egress change by {{AccountName}} from {{SourceIpAddress}}"
        },
        "alertRuleTemplateName": "4f19d4e3-ec5f-4abc-9e61-819eb131758c",
        "customDetails": {
          "AWSRegion": "AWSRegion",
          "EventName": "EventName",
          "UserAgent": "UserAgent",
          "UserIdentityArn": "UserIdentityArn",
          "UserIdentityType": "UserIdentityType",
          "UserIdentityUserName": "UserIdentityUserName"
        },
        "description": "A Security Group acts as a virtual firewall for an AWS instance to control inbound and outbound traffic. This rule detects AWS CloudTrail events for changes to Security Group ingress and egress settings.\nInvestigate to validate the legitimacy of the activity and identify potential malicious activity.\n",
        "displayName": "AWSCloudTrail - Changes to AWS Security Group ingress and egress settings",
        "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%20Web%20Services/Analytic%20Rules/AWS_IngressEgressSecurityGroupChange.yaml",
        "query": "let EventNameList = dynamic([ \"AuthorizeSecurityGroupEgress\", \"AuthorizeSecurityGroupIngress\", \"RevokeSecurityGroupEgress\", \"RevokeSecurityGroupIngress\"]);\nAWSCloudTrail\n| where EventName in~ (EventNameList)\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 EventCount=count(), StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated)\nby EventSource, EventName, UserIdentityType, RecipientAccountId, AccountName, AccountUPNSuffix, SourceIpAddress, UserAgent, SessionMfaAuthenticated, AWSRegion,\nAdditionalEventData, UserIdentityAccountId, UserIdentityPrincipalid, ResponseElements\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Low",
        "status": "Available",
        "subTechniques": [
          "T1562.007"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1562"
        ],
        "templateVersion": "1.0.5",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}