Microsoft Sentinel Analytic Rules
cloudbrothers.infoAzure Sentinel RepoToggle Dark/Light/Auto modeToggle Dark/Light/Auto modeToggle Dark/Light/Auto modeBack to homepage

AWSCloudTrail - Creation of EC2 policy and then privilege escalation

Back
Ida694e977-740c-4578-9f8f-5e39029f1d23
RulenameAWSCloudTrail - Creation of EC2 policy and then privilege escalation
DescriptionIdentifies creation of IAM policies that grant broad EC2 permissions or EC2 actions combined with IAM pass-role

capability, followed by policy attachment activity. This pattern can indicate attempts to gain elevated cloud

execution privileges and should be validated as authorized change activity.
SeverityHigh
TacticsDefenseEvasion
PrivilegeEscalation
Persistence
TechniquesT1484
T1098.003
Required data connectorsAWS
KindScheduled
Query frequency1d
Query period1d
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_CreatedEC2PolicytoPrivilegeEscalation.yaml
Version1.0.4
Arm templatea694e977-740c-4578-9f8f-5e39029f1d23.json
Deploy To Azure
let EventNameList = dynamic(["AttachUserPolicy","AttachRolePolicy","AttachGroupPolicy"]);
let createPolicy =  dynamic(["CreatePolicy", "CreatePolicyVersion"]);
let timeframe = 1d;
let lookback = 14d;
// Creating Master table with all the events to use with materialize for better performance
let EventInfo = AWSCloudTrail
| where TimeGenerated >= ago(lookback)
| where EventName in (EventNameList) or EventName in (createPolicy)
| 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]), "");
//Checking for Policy creation event with Full Admin Privileges since lookback period.
let FullAdminPolicyEvents =  materialize(  EventInfo
| where TimeGenerated >= ago(lookback)
| where EventName in (createPolicy)
| 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 == ""
| distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, UserIdentityArn, RecipientAccountId, AccountName, AccountUPNSuffix
| project-rename StartTime = TimeGenerated  );
let PolicyAttach = materialize(  EventInfo
| where TimeGenerated >= ago(timeframe)
| where EventName in (EventNameList) and isempty(ErrorCode) and isempty(ErrorMessage)
| extend PolicyName = tostring(split(tostring(parse_json(RequestParameters).policyArn),"/")[1])
| summarize AttachEventCount=count(), StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by EventSource, EventName,   UserIdentityType , UserIdentityArn, SourceIpAddress, RecipientAccountId, AccountName, AccountUPNSuffix, PolicyName
| extend AttachEvent = pack("StartTime", StartTime, "EndTime", EndTime, "EventName", EventName, "UserIdentityType",   UserIdentityType,  "AccountName", AccountName, "AccountUPNSuffix", AccountUPNSuffix, "RecipientAccountId", RecipientAccountId, "UserIdentityArn", UserIdentityArn, "SourceIpAddress", SourceIpAddress)
| project EventSource, PolicyName, AttachEvent, RecipientAccountId, AccountName, AccountUPNSuffix, AttachEventCount
);
// Joining the list of PolicyNames and checking if it has been attached to any Roles/Users/Groups.
// These Roles/Users/Groups will be Privileged and can be used by adversaries as pivot point for privilege escalation via multiple ways.
FullAdminPolicyEvents
| join kind=leftouter
(
    PolicyAttach
)
on PolicyName
| project-away PolicyName1
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
tactics:
- DefenseEvasion
- PrivilegeEscalation
- Persistence
requiredDataConnectors:
- dataTypes:
  - AWSCloudTrail
  connectorId: AWS
alertDetailsOverride:
  alertDisplayNameFormat: 'AWS EC2 privilege escalation policy activity: {{PolicyName}} by {{AccountName}}'
  alertDescriptionFormat: Detected {{EventName}} for policy {{PolicyName}} in account {{RecipientAccountId}}.
id: a694e977-740c-4578-9f8f-5e39029f1d23
severity: High
status: Available
customDetails:
  RecipientAccountId: RecipientAccountId
  UserIdentityArn: UserIdentityArn
  EventName: EventName
  PolicyName: PolicyName
query: |
  let EventNameList = dynamic(["AttachUserPolicy","AttachRolePolicy","AttachGroupPolicy"]);
  let createPolicy =  dynamic(["CreatePolicy", "CreatePolicyVersion"]);
  let timeframe = 1d;
  let lookback = 14d;
  // Creating Master table with all the events to use with materialize for better performance
  let EventInfo = AWSCloudTrail
  | where TimeGenerated >= ago(lookback)
  | where EventName in (EventNameList) or EventName in (createPolicy)
  | 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]), "");
  //Checking for Policy creation event with Full Admin Privileges since lookback period.
  let FullAdminPolicyEvents =  materialize(  EventInfo
  | where TimeGenerated >= ago(lookback)
  | where EventName in (createPolicy)
  | 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 == ""
  | distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, UserIdentityArn, RecipientAccountId, AccountName, AccountUPNSuffix
  | project-rename StartTime = TimeGenerated  );
  let PolicyAttach = materialize(  EventInfo
  | where TimeGenerated >= ago(timeframe)
  | where EventName in (EventNameList) and isempty(ErrorCode) and isempty(ErrorMessage)
  | extend PolicyName = tostring(split(tostring(parse_json(RequestParameters).policyArn),"/")[1])
  | summarize AttachEventCount=count(), StartTime = min(TimeGenerated), EndTime = max(TimeGenerated) by EventSource, EventName,   UserIdentityType , UserIdentityArn, SourceIpAddress, RecipientAccountId, AccountName, AccountUPNSuffix, PolicyName
  | extend AttachEvent = pack("StartTime", StartTime, "EndTime", EndTime, "EventName", EventName, "UserIdentityType",   UserIdentityType,  "AccountName", AccountName, "AccountUPNSuffix", AccountUPNSuffix, "RecipientAccountId", RecipientAccountId, "UserIdentityArn", UserIdentityArn, "SourceIpAddress", SourceIpAddress)
  | project EventSource, PolicyName, AttachEvent, RecipientAccountId, AccountName, AccountUPNSuffix, AttachEventCount
  );
  // Joining the list of PolicyNames and checking if it has been attached to any Roles/Users/Groups.
  // These Roles/Users/Groups will be Privileged and can be used by adversaries as pivot point for privilege escalation via multiple ways.
  FullAdminPolicyEvents
  | join kind=leftouter
  (
      PolicyAttach
  )
  on PolicyName
  | project-away PolicyName1  
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_CreatedEC2PolicytoPrivilegeEscalation.yaml
kind: Scheduled
queryPeriod: 1d
version: 1.0.4
name: AWSCloudTrail - Creation of EC2 policy and then privilege escalation
queryFrequency: 1d
triggerThreshold: 0
relevantTechniques:
- T1484
- T1098.003
description: |
  Identifies creation of IAM policies that grant broad EC2 permissions or EC2 actions combined with IAM pass-role
  capability, followed by policy attachment activity. This pattern can indicate attempts to gain elevated cloud
  execution privileges and should be validated as authorized change activity.  
triggerOperator: gt