S3 bucket exposed via policy
Id | 44a5b65e-b0a9-4591-aabc-388fd92a28c4 |
Rulename | S3 bucket exposed via policy |
Description | Detected S3 bucket publicly exposed via policy, this could lead for sensitive information leakage to the public. Verify the S3 object configurations. |
Severity | Medium |
Tactics | Exfiltration |
Techniques | T1537 |
Required data connectors | AWS |
Kind | Scheduled |
Query frequency | 1h |
Query period | 1h |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_S3BucketExposedviaPolicy.yaml |
Version | 1.0.0 |
Arm template | 44a5b65e-b0a9-4591-aabc-388fd92a28c4.json |
AWSCloudTrail
| where EventName == "PutBucketPolicy" and isempty(ErrorCode) and isempty(ErrorMessage)
| extend Statement = parse_json(tostring((parse_json(RequestParameters).bucketPolicy))).Statement
| mvexpand Statement
| extend Action = parse_json(Statement).Action , Effect = tostring(parse_json(Statement).Effect), Resource = tostring(parse_json(Statement).Resource), Condition = tostring(parse_json(Statement).Condition), Principal_aws = tostring(parse_json(Statement).Principal.AWS), Principal = tostring(parse_json(Statement).Principal)
| extend Action = tostring(Action)
| where Effect =~ "Allow" and (Principal_aws == "*" or Principal == "*") and isempty(Condition)
| distinct TimeGenerated, EventName, SourceIpAddress, UserIdentityArn, UserIdentityUserName
| extend UserIdentityUserName = iff(isnotempty(UserIdentityUserName), UserIdentityUserName, tostring(split(UserIdentityArn,'/')[-1]))
| extend timestamp = TimeGenerated, IPCustomEntity = SourceIpAddress, AccountCustomEntity = UserIdentityUserName
triggerOperator: gt
version: 1.0.0
query: |
AWSCloudTrail
| where EventName == "PutBucketPolicy" and isempty(ErrorCode) and isempty(ErrorMessage)
| extend Statement = parse_json(tostring((parse_json(RequestParameters).bucketPolicy))).Statement
| mvexpand Statement
| extend Action = parse_json(Statement).Action , Effect = tostring(parse_json(Statement).Effect), Resource = tostring(parse_json(Statement).Resource), Condition = tostring(parse_json(Statement).Condition), Principal_aws = tostring(parse_json(Statement).Principal.AWS), Principal = tostring(parse_json(Statement).Principal)
| extend Action = tostring(Action)
| where Effect =~ "Allow" and (Principal_aws == "*" or Principal == "*") and isempty(Condition)
| distinct TimeGenerated, EventName, SourceIpAddress, UserIdentityArn, UserIdentityUserName
| extend UserIdentityUserName = iff(isnotempty(UserIdentityUserName), UserIdentityUserName, tostring(split(UserIdentityArn,'/')[-1]))
| extend timestamp = TimeGenerated, IPCustomEntity = SourceIpAddress, AccountCustomEntity = UserIdentityUserName
status: Available
entityMappings:
- entityType: Account
fieldMappings:
- columnName: AccountCustomEntity
identifier: FullName
- entityType: IP
fieldMappings:
- columnName: IPCustomEntity
identifier: Address
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_S3BucketExposedviaPolicy.yaml
queryFrequency: 1h
requiredDataConnectors:
- connectorId: AWS
dataTypes:
- AWSCloudTrail
name: S3 bucket exposed via policy
queryPeriod: 1h
severity: Medium
kind: Scheduled
tactics:
- Exfiltration
id: 44a5b65e-b0a9-4591-aabc-388fd92a28c4
description: |
'Detected S3 bucket publicly exposed via policy, this could lead for sensitive information leakage to the public. Verify the S3 object configurations.'
relevantTechniques:
- T1537
triggerThreshold: 0
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/44a5b65e-b0a9-4591-aabc-388fd92a28c4')]",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/44a5b65e-b0a9-4591-aabc-388fd92a28c4')]",
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules",
"kind": "Scheduled",
"apiVersion": "2022-11-01-preview",
"properties": {
"displayName": "S3 bucket exposed via policy",
"description": "'Detected S3 bucket publicly exposed via policy, this could lead for sensitive information leakage to the public. Verify the S3 object configurations.'\n",
"severity": "Medium",
"enabled": true,
"query": "AWSCloudTrail\n| where EventName == \"PutBucketPolicy\" and isempty(ErrorCode) and isempty(ErrorMessage)\n| extend Statement = parse_json(tostring((parse_json(RequestParameters).bucketPolicy))).Statement\n| mvexpand Statement\n| extend Action = parse_json(Statement).Action , Effect = tostring(parse_json(Statement).Effect), Resource = tostring(parse_json(Statement).Resource), Condition = tostring(parse_json(Statement).Condition), Principal_aws = tostring(parse_json(Statement).Principal.AWS), Principal = tostring(parse_json(Statement).Principal)\n| extend Action = tostring(Action)\n| where Effect =~ \"Allow\" and (Principal_aws == \"*\" or Principal == \"*\") and isempty(Condition)\n| distinct TimeGenerated, EventName, SourceIpAddress, UserIdentityArn, UserIdentityUserName\n| extend UserIdentityUserName = iff(isnotempty(UserIdentityUserName), UserIdentityUserName, tostring(split(UserIdentityArn,'/')[-1]))\n| extend timestamp = TimeGenerated, IPCustomEntity = SourceIpAddress, AccountCustomEntity = UserIdentityUserName\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0,
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Exfiltration"
],
"techniques": [
"T1537"
],
"alertRuleTemplateName": "44a5b65e-b0a9-4591-aabc-388fd92a28c4",
"customDetails": null,
"entityMappings": [
{
"fieldMappings": [
{
"columnName": "AccountCustomEntity",
"identifier": "FullName"
}
],
"entityType": "Account"
},
{
"fieldMappings": [
{
"columnName": "IPCustomEntity",
"identifier": "Address"
}
],
"entityType": "IP"
}
],
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_S3BucketExposedviaPolicy.yaml",
"status": "Available",
"templateVersion": "1.0.0"
}
}
]
}