AWSCloudTrail - Privilege escalation via EC2 policy

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Id	a2b2a984-c820-4d93-830e-139bffd81fa3
Rulename	AWSCloudTrail - Privilege escalation via EC2 policy
Description	Detects inline IAM policy updates that grant broad EC2 permissions or EC2 actions paired with IAM pass-role capability. This policy pattern can enable launch and control of compute resources as a privilege escalation path.
Severity	Medium
Tactics	PrivilegeEscalation
Techniques	T1098.003
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_PrivilegeEscalationViaEC2Policy.yaml
Version	1.0.2
Arm template	a2b2a984-c820-4d93-830e-139bffd81fa3.json

KQL

AWSCloudTrail
  | where EventName in ("PutUserPolicy","PutRolePolicy","PutGroupPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
  | extend PolicyName = tostring(parse_json(RequestParameters).policyName)
  | extend Statement = parse_json(tostring((parse_json(RequestParameters).policyDocument))).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)
  | extend Action = tostring(Action)
  | where Effect =~ "Allow" and ((((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "ec2:*") or ((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "ec2:RunInstances") or ((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "ec2:Run*")) or (Action contains "ec2:*") or (Action contains "ec2:ListInstances" and Action contains "ec2:StartInstance" and Action contains "ec2:ModifyInstanceAttribute") or (Action contains "ec2:List*" and Action contains "ec2:Start*" and Action contains "ec2:Modify*")) and Resource == "*" and Condition == ""
  | 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]), "")
  | distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, UserIdentityArn, UserIdentityUserName, RecipientAccountId, AccountName, AccountUPNSuffix

YAML

status: Available
queryFrequency: 1d
queryPeriod: 1d
triggerOperator: gt
query: |
  AWSCloudTrail
    | where EventName in ("PutUserPolicy","PutRolePolicy","PutGroupPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
    | extend PolicyName = tostring(parse_json(RequestParameters).policyName)
    | extend Statement = parse_json(tostring((parse_json(RequestParameters).policyDocument))).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)
    | extend Action = tostring(Action)
    | where Effect =~ "Allow" and ((((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "ec2:*") or ((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "ec2:RunInstances") or ((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "ec2:Run*")) or (Action contains "ec2:*") or (Action contains "ec2:ListInstances" and Action contains "ec2:StartInstance" and Action contains "ec2:ModifyInstanceAttribute") or (Action contains "ec2:List*" and Action contains "ec2:Start*" and Action contains "ec2:Modify*")) and Resource == "*" and Condition == ""
    | 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]), "")
    | distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, UserIdentityArn, UserIdentityUserName, RecipientAccountId, AccountName, AccountUPNSuffix  
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_PrivilegeEscalationViaEC2Policy.yaml
tactics:
- PrivilegeEscalation
triggerThreshold: 0
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
alertDetailsOverride:
  alertDescriptionFormat: Detected {{EventName}} Event, updating inline EC2 escalation policy {{PolicyName}} in account {{RecipientAccountId}}.
  alertDisplayNameFormat: AWS EC2 privilege escalation policy update by {{AccountName}}
relevantTechniques:
- T1098.003
customDetails:
  UserIdentityArn: UserIdentityArn
  EventName: EventName
  PolicyName: PolicyName
  RecipientAccountId: RecipientAccountId
description: |
  Detects inline IAM policy updates that grant broad EC2 permissions or EC2 actions paired with IAM pass-role
  capability. This policy pattern can enable launch and control of compute resources as a privilege escalation path.  
name: AWSCloudTrail - Privilege escalation via EC2 policy
version: 1.0.2
kind: Scheduled
id: a2b2a984-c820-4d93-830e-139bffd81fa3
severity: Medium

ARM