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 | 1.0.4 |
Arm template | 60dfc193-0f73-4279-b43c-110ade02b201.json |
let kmsActions = dynamic(["kms:Encrypt", "kms:*"]); //Add other overly permissive APIs to this list.
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 has_any (kmsActions) 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
relevantTechniques:
- T1486
severity: High
id: 60dfc193-0f73-4279-b43c-110ade02b201
triggerThreshold: 0
kind: Scheduled
queryFrequency: 1d
version: 1.0.4
status: Available
query: |
let kmsActions = dynamic(["kms:Encrypt", "kms:*"]); //Add other overly permissive APIs to this list.
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 has_any (kmsActions) 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
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.'
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_OverlyPermessiveKMS.yaml
queryPeriod: 1d
entityMappings:
- fieldMappings:
- identifier: Name
columnName: AccountName
- identifier: UPNSuffix
columnName: AccountUPNSuffix
- identifier: CloudAppAccountId
columnName: RecipientAccountId
entityType: Account
- fieldMappings:
- identifier: Address
columnName: SourceIpAddress
entityType: IP
name: Suspicious overly permissive KMS key policy created
requiredDataConnectors:
- connectorId: AWS
dataTypes:
- AWSCloudTrail
tactics:
- Impact
{
"$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/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": "let kmsActions = dynamic([\"kms:Encrypt\", \"kms:*\"]); //Add other overly permissive APIs to this list.\nAWSCloudTrail\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 has_any (kmsActions) 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",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"Impact"
],
"techniques": [
"T1486"
],
"templateVersion": "1.0.4",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}