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Cisco - firewall block but success logon to Microsoft Entra ID

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Id157c0cfc-d76d-463b-8755-c781608cdc1a
RulenameCisco - firewall block but success logon to Microsoft Entra ID
DescriptionCorrelate IPs blocked by a Cisco firewall appliance with successful Microsoft Entra ID signins.

Because the IP was blocked by the firewall, that same IP logging on successfully to Entra ID is potentially suspect

and could indicate credential compromise for the user account.
SeverityMedium
TacticsInitialAccess
TechniquesT1078
Required data connectorsAzureActiveDirectory
CiscoASA
KindScheduled
Query frequency1d
Query period1d
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/SigninFirewallCorrelation.yaml
Version1.0.5
Arm template157c0cfc-d76d-463b-8755-c781608cdc1a.json
Deploy To Azure
let aadFunc = (tableName:string){
CommonSecurityLog
| where DeviceVendor =~ "Cisco"
| where DeviceAction =~ "denied"
| where ipv4_is_private(SourceIP) == false
| summarize count() by SourceIP
| join (
    // Successful signins from IPs blocked by the firewall solution are suspect
    // Include fully successful sign-ins, but also ones that failed only at MFA stage
    // as that supposes the password was sucessfully guessed.
  table(tableName)
  | where ResultType in ("0", "50074", "50076")
) on $left.SourceIP == $right.IPAddress
| extend AccountName = tostring(split(Account, "@")[0]), AccountUPNSuffix = tostring(split(Account, "@")[1])
};
let aadSignin = aadFunc("SigninLogs");
let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
union isfuzzy=true aadSignin, aadNonInt
queryFrequency: 1d
severity: Medium
id: 157c0cfc-d76d-463b-8755-c781608cdc1a
requiredDataConnectors:
- dataTypes:
  - CommonSecurityLog
  connectorId: CiscoASA
- dataTypes:
  - SigninLogs
  connectorId: AzureActiveDirectory
- dataTypes:
  - AADNonInteractiveUserSignInLogs
  connectorId: AzureActiveDirectory
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/SigninFirewallCorrelation.yaml
kind: Scheduled
description: |
  'Correlate IPs blocked by a Cisco firewall appliance with successful Microsoft Entra ID signins.
  Because the IP was blocked by the firewall, that same IP logging on successfully to Entra ID is potentially suspect
  and could indicate credential compromise for the user account.'  
query: |
  let aadFunc = (tableName:string){
  CommonSecurityLog
  | where DeviceVendor =~ "Cisco"
  | where DeviceAction =~ "denied"
  | where ipv4_is_private(SourceIP) == false
  | summarize count() by SourceIP
  | join (
      // Successful signins from IPs blocked by the firewall solution are suspect
      // Include fully successful sign-ins, but also ones that failed only at MFA stage
      // as that supposes the password was sucessfully guessed.
    table(tableName)
    | where ResultType in ("0", "50074", "50076")
  ) on $left.SourceIP == $right.IPAddress
  | extend AccountName = tostring(split(Account, "@")[0]), AccountUPNSuffix = tostring(split(Account, "@")[1])
  };
  let aadSignin = aadFunc("SigninLogs");
  let aadNonInt = aadFunc("AADNonInteractiveUserSignInLogs");
  union isfuzzy=true aadSignin, aadNonInt  
tactics:
- InitialAccess
triggerThreshold: 0
triggerOperator: gt
metadata:
  categories:
    domains:
    - Security - Network
  source:
    kind: Community
  support:
    tier: Community
  author:
    name: Microsoft Security Resarch
relevantTechniques:
- T1078
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: FullName
    columnName: UserPrincipalName
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: SourceIP
version: 1.0.5
name: Cisco - firewall block but success logon to Microsoft Entra ID
queryPeriod: 1d
{
  "$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/157c0cfc-d76d-463b-8755-c781608cdc1a')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/157c0cfc-d76d-463b-8755-c781608cdc1a')]",
      "properties": {
        "alertRuleTemplateName": "157c0cfc-d76d-463b-8755-c781608cdc1a",
        "customDetails": null,
        "description": "'Correlate IPs blocked by a Cisco firewall appliance with successful Microsoft Entra ID signins.\nBecause the IP was blocked by the firewall, that same IP logging on successfully to Entra ID is potentially suspect\nand could indicate credential compromise for the user account.'\n",
        "displayName": "Cisco - firewall block but success logon to Microsoft Entra ID",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserPrincipalName",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SourceIP",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/MultipleDataSources/SigninFirewallCorrelation.yaml",
        "query": "let aadFunc = (tableName:string){\nCommonSecurityLog\n| where DeviceVendor =~ \"Cisco\"\n| where DeviceAction =~ \"denied\"\n| where ipv4_is_private(SourceIP) == false\n| summarize count() by SourceIP\n| join (\n    // Successful signins from IPs blocked by the firewall solution are suspect\n    // Include fully successful sign-ins, but also ones that failed only at MFA stage\n    // as that supposes the password was sucessfully guessed.\n  table(tableName)\n  | where ResultType in (\"0\", \"50074\", \"50076\")\n) on $left.SourceIP == $right.IPAddress\n| extend AccountName = tostring(split(Account, \"@\")[0]), AccountUPNSuffix = tostring(split(Account, \"@\")[1])\n};\nlet aadSignin = aadFunc(\"SigninLogs\");\nlet aadNonInt = aadFunc(\"AADNonInteractiveUserSignInLogs\");\nunion isfuzzy=true aadSignin, aadNonInt\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "techniques": [
          "T1078"
        ],
        "templateVersion": "1.0.5",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}