Suspicious overly permissive KMS key policy created
Id | 60dfc193-0f73-4279-b43c-110ade02b201 |
Rulename | Suspicious overly permissive KMS key policy created |
Description | An overly permissive key policy was created, resulting in KMS keys where the kms:Encrypt action is accessible to everyone (even outside of the organization). This could mean that your account is compromised and that the attacker is using the encryption key to compromise other organizations. |
Severity | High |
Tactics | Impact |
Techniques | T1486 |
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_OverlyPermessiveKMS.yaml |
Version | 1.0.2 |
Arm template | 60dfc193-0f73-4279-b43c-110ade02b201.json |
AWSCloudTrail
| where EventName in ("CreateKey","PutKeyPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
| extend Statement = parse_json(tostring((parse_json(RequestParameters).policy))).Statement
| mvexpand Statement
| extend Action = tostring(parse_json(Statement).Action), Effect = tostring(parse_json(Statement).Effect), Principal = iff(isnotempty(tostring(parse_json(Statement).Principal.AWS)),tostring(parse_json(Statement).Principal.AWS), tostring(parse_json(Statement).Principal))
| where Effect =~ "Allow" and (Action == "kms:Encrypt" or Action == "kms:*") and Principal == "*"
| 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
severity: High
relevantTechniques:
- T1486
queryFrequency: 1d
kind: Scheduled
version: 1.0.2
name: Suspicious overly permissive KMS key policy created
triggerOperator: gt
description: |
'An overly permissive key policy was created, resulting in KMS keys where the kms:Encrypt action is accessible to everyone (even outside of the organization). This could mean that your account is compromised and that the attacker is using the encryption key to compromise other organizations.'
queryPeriod: 1d
query: |
AWSCloudTrail
| where EventName in ("CreateKey","PutKeyPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
| extend Statement = parse_json(tostring((parse_json(RequestParameters).policy))).Statement
| mvexpand Statement
| extend Action = tostring(parse_json(Statement).Action), Effect = tostring(parse_json(Statement).Effect), Principal = iff(isnotempty(tostring(parse_json(Statement).Principal.AWS)),tostring(parse_json(Statement).Principal.AWS), tostring(parse_json(Statement).Principal))
| where Effect =~ "Allow" and (Action == "kms:Encrypt" or Action == "kms:*") and Principal == "*"
| 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
entityMappings:
- entityType: Account
fieldMappings:
- columnName: AccountName
identifier: Name
- columnName: AccountUPNSuffix
identifier: UPNSuffix
- columnName: RecipientAccountId
identifier: CloudAppAccountId
- entityType: IP
fieldMappings:
- columnName: SourceIpAddress
identifier: Address
tactics:
- Impact
status: Available
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_OverlyPermessiveKMS.yaml
id: 60dfc193-0f73-4279-b43c-110ade02b201
requiredDataConnectors:
- dataTypes:
- AWSCloudTrail
connectorId: AWS
{
"$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/60dfc193-0f73-4279-b43c-110ade02b201')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/60dfc193-0f73-4279-b43c-110ade02b201')]",
"properties": {
"alertRuleTemplateName": "60dfc193-0f73-4279-b43c-110ade02b201",
"customDetails": null,
"description": "'An overly permissive key policy was created, resulting in KMS keys where the kms:Encrypt action is accessible to everyone (even outside of the organization). This could mean that your account is compromised and that the attacker is using the encryption key to compromise other organizations.'\n",
"displayName": "Suspicious overly permissive KMS key policy created",
"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_OverlyPermessiveKMS.yaml",
"query": "AWSCloudTrail\n| where EventName in (\"CreateKey\",\"PutKeyPolicy\") and isempty(ErrorCode) and isempty(ErrorMessage)\n| extend Statement = parse_json(tostring((parse_json(RequestParameters).policy))).Statement\n| mvexpand Statement\n| extend Action = tostring(parse_json(Statement).Action), Effect = tostring(parse_json(Statement).Effect), Principal = iff(isnotempty(tostring(parse_json(Statement).Principal.AWS)),tostring(parse_json(Statement).Principal.AWS), tostring(parse_json(Statement).Principal))\n| where Effect =~ \"Allow\" and (Action == \"kms:Encrypt\" or Action == \"kms:*\") and Principal == \"*\"\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": [
"Impact"
],
"techniques": [
"T1486"
],
"templateVersion": "1.0.2",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}