Network ACL with all the open ports to a specified CIDR

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Id	f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281
Rulename	Network ACL with all the open ports to a specified CIDR
Description	Detected network ACL with all the ports open to a specified CIDR. This could lead to potential lateral movements or initial access attacks. Make sure to mitigate this risk.
Severity	High
Tactics	DefenseEvasion
Techniques	T1562
Required data connectors	AWS
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_NetworkACLOpenToAllPorts.yaml
Version	1.0.2
Arm template	f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281.json

KQL

AWSCloudTrail
| where EventName in ('CreateNetworkAclEntry', 'ReplaceNetworkAclEntry') and isempty(ErrorMessage) and isempty(ErrorCode)
| extend ruleAction = tostring(parse_json(RequestParameters)['ruleAction']),
         egress=parse_json(RequestParameters)['egress'],
         total_ports=(toint(parse_json(parse_json(RequestParameters)['portRange'])['to']) - toint(parse_json(parse_json(RequestParameters)['portRange'])['from'])),
         aclProtocol=parse_json(RequestParameters)['aclProtocol']
| where isnotempty(total_ports)
| where ruleAction == 'allow' and egress == false and (aclProtocol == '-1' or (total_ports > 1024))
| 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]), "")
| extend timestamp = TimeGenerated

YAML

relevantTechniques:
- T1562
name: Network ACL with all the open ports to a specified CIDR
requiredDataConnectors:
- dataTypes:
  - AWSCloudTrail
  connectorId: AWS
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP
triggerThreshold: 0
id: f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281
tactics:
- DefenseEvasion
version: 1.0.2
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_NetworkACLOpenToAllPorts.yaml
queryPeriod: 1d
kind: Scheduled
queryFrequency: 1d
severity: High
status: Available
description: |
    'Detected network ACL with all the ports open to a specified CIDR. This could lead to potential lateral movements or initial access attacks. Make sure to mitigate this risk.'
query: |
  AWSCloudTrail
  | where EventName in ('CreateNetworkAclEntry', 'ReplaceNetworkAclEntry') and isempty(ErrorMessage) and isempty(ErrorCode)
  | extend ruleAction = tostring(parse_json(RequestParameters)['ruleAction']),
           egress=parse_json(RequestParameters)['egress'],
           total_ports=(toint(parse_json(parse_json(RequestParameters)['portRange'])['to']) - toint(parse_json(parse_json(RequestParameters)['portRange'])['from'])),
           aclProtocol=parse_json(RequestParameters)['aclProtocol']
  | where isnotempty(total_ports)
  | where ruleAction == 'allow' and egress == false and (aclProtocol == '-1' or (total_ports > 1024))
  | 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]), "")
  | extend timestamp = TimeGenerated  
triggerOperator: gt

ARM

{
  "$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/f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281')]",
      "properties": {
        "alertRuleTemplateName": "f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281",
        "customDetails": null,
        "description": "'Detected network ACL with all the ports open to a specified CIDR. This could lead to potential lateral movements or initial access attacks. Make sure to mitigate this risk.'\n",
        "displayName": "Network ACL with all the open ports to a specified CIDR",
        "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_NetworkACLOpenToAllPorts.yaml",
        "query": "AWSCloudTrail\n| where EventName in ('CreateNetworkAclEntry', 'ReplaceNetworkAclEntry') and isempty(ErrorMessage) and isempty(ErrorCode)\n| extend ruleAction = tostring(parse_json(RequestParameters)['ruleAction']),\n         egress=parse_json(RequestParameters)['egress'],\n         total_ports=(toint(parse_json(parse_json(RequestParameters)['portRange'])['to']) - toint(parse_json(parse_json(RequestParameters)['portRange'])['from'])),\n         aclProtocol=parse_json(RequestParameters)['aclProtocol']\n| where isnotempty(total_ports)\n| where ruleAction == 'allow' and egress == false and (aclProtocol == '-1' or (total_ports > 1024))\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| extend timestamp = TimeGenerated\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "High",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1562"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}