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

triggerOperator: gt
queryFrequency: 1d
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.'
status: Available
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
version: 1.0.2
queryPeriod: 1d
name: Network ACL with all the open ports to a specified CIDR
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_NetworkACLOpenToAllPorts.yaml
id: f8ea7d50-e33b-4b9d-9c3e-a59fcbcee281
tactics:
- DefenseEvasion
relevantTechniques:
- T1562
severity: High
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP
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

ARM

{
  "$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/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",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "techniques": [
          "T1562"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}