Tag Archives: service-linked roles

Amazon GuardDuty – Continuous Security Monitoring & Threat Detection

Post Syndicated from Jeff Barr original https://aws.amazon.com/blogs/aws/amazon-guardduty-continuous-security-monitoring-threat-detection/

Threats to your IT infrastructure (AWS accounts & credentials, AWS resources, guest operating systems, and applications) come in all shapes and sizes! The online world can be a treacherous place and we want to make sure that you have the tools, knowledge, and perspective to keep your IT infrastructure safe & sound.

Amazon GuardDuty is designed to give you just that. Informed by a multitude of public and AWS-generated data feeds and powered by machine learning, GuardDuty analyzes billions of events in pursuit of trends, patterns, and anomalies that are recognizable signs that something is amiss. You can enable it with a click and see the first findings within minutes.

How it Works
GuardDuty voraciously consumes multiple data streams, including several threat intelligence feeds, staying aware of malicious IP addresses, devious domains, and more importantly, learning to accurately identify malicious or unauthorized behavior in your AWS accounts. In combination with information gleaned from your VPC Flow Logs, AWS CloudTrail Event Logs, and DNS logs, this allows GuardDuty to detect many different types of dangerous and mischievous behavior including probes for known vulnerabilities, port scans and probes, and access from unusual locations. On the AWS side, it looks for suspicious AWS account activity such as unauthorized deployments, unusual CloudTrail activity, patterns of access to AWS API functions, and attempts to exceed multiple service limits. GuardDuty will also look for compromised EC2 instances talking to malicious entities or services, data exfiltration attempts, and instances that are mining cryptocurrency.

GuardDuty operates completely on AWS infrastructure and does not affect the performance or reliability of your workloads. You do not need to install or manage any agents, sensors, or network appliances. This clean, zero-footprint model should appeal to your security team and allow them to green-light the use of GuardDuty across all of your AWS accounts.

Findings are presented to you at one of three levels (low, medium, or high), accompanied by detailed evidence and recommendations for remediation. The findings are also available as Amazon CloudWatch Events; this allows you to use your own AWS Lambda functions to automatically remediate specific types of issues. This mechanism also allows you to easily push GuardDuty findings into event management systems such as Splunk, Sumo Logic, and PagerDuty and to workflow systems like JIRA, ServiceNow, and Slack.

A Quick Tour
Let’s take a quick tour. I open up the GuardDuty Console and click on Get started:

Then I confirm that I want to enable GuardDuty. This gives it permission to set up the appropriate service-linked roles and to analyze my logs by clicking on Enable GuardDuty:

My own AWS environment isn’t all that exciting, so I visit the General Settings and click on Generate sample findings to move ahead. Now I’ve got some intriguing findings:

I can click on a finding to learn more:

The magnifying glass icons allow me to create inclusion or exclusion filters for the associated resource, action, or other value. I can filter for all of the findings related to this instance:

I can customize GuardDuty by adding lists of trusted IP addresses and lists of malicious IP addresses that are peculiar to my environment:

After I enable GuardDuty in my administrator account, I can invite my other accounts to participate:

Once the accounts decide to participate, GuardDuty will arrange for their findings to be shared with the administrator account.

I’ve barely scratched the surface of GuardDuty in the limited space and time that I have. You can try it out at no charge for 30 days; after that you pay based on the number of entries it processes from your VPC Flow, CloudTrail, and DNS logs.

Available Now
Amazon GuardDuty is available in production form in the US East (Northern Virginia), US East (Ohio), US West (Oregon), US West (Northern California), EU (Ireland), EU (Frankfurt), EU (London), South America (São Paulo), Canada (Central), Asia Pacific (Tokyo), Asia Pacific (Seoul), Asia Pacific (Singapore), Asia Pacific (Sydney), and Asia Pacific (Mumbai) Regions and you can start using it today!

Jeff;

Now Use AWS IAM to Delete a Service-Linked Role When You No Longer Require an AWS Service to Perform Actions on Your Behalf

Post Syndicated from Ujjwal Pugalia original https://aws.amazon.com/blogs/security/now-use-aws-iam-to-delete-a-service-linked-role-when-you-no-longer-require-an-aws-service-to-perform-actions-on-your-behalf/

Earlier this year, AWS Identity and Access Management (IAM) introduced service-linked roles, which provide you an easy and secure way to delegate permissions to AWS services. Each service-linked role delegates permissions to an AWS service, which is called its linked service. Service-linked roles help with monitoring and auditing requirements by providing a transparent way to understand all actions performed on your behalf because AWS CloudTrail logs all actions performed by the linked service using service-linked roles. For information about which services support service-linked roles, see AWS Services That Work with IAM. Over time, more AWS services will support service-linked roles.

Today, IAM added support for the deletion of service-linked roles through the IAM console and the IAM API/CLI. This means you now can revoke permissions from the linked service to create and manage AWS resources in your account. When you delete a service-linked role, the linked service no longer has the permissions to perform actions on your behalf. To ensure your AWS services continue to function as expected when you delete a service-linked role, IAM validates that you no longer have resources that require the service-linked role to function properly. This prevents you from inadvertently revoking permissions required by an AWS service to manage your existing AWS resources and helps you maintain your resources in a consistent state. If there are any resources in your account that require the service-linked role, you will receive an error when you attempt to delete the service-linked role, and the service-linked role will remain in your account. If you do not have any resources that require the service-linked role, you can delete the service-linked role and IAM will remove the service-linked role from your account.

In this blog post, I show how to delete a service-linked role by using the IAM console. To learn more about how to delete service-linked roles by using the IAM API/CLI, see the DeleteServiceLinkedRole API documentation.

Note: The IAM console does not currently support service-linked role deletion for Amazon Lex, but you can delete your service-linked role by using the Amazon Lex console. To learn more, see Service Permissions.

How to delete a service-linked role by using the IAM console

If you no longer need to use an AWS service that uses a service-linked role, you can remove permissions from that service by deleting the service-linked role through the IAM console. To delete a service-linked role, you must have permissions for the iam:DeleteServiceLinkedRole action. For example, the following IAM policy grants the permission to delete service-linked roles used by Amazon Redshift. To learn more about working with IAM policies, see Working with Policies.

{ 
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "AllowDeletionOfServiceLinkedRolesForRedshift",
            "Effect": "Allow",
            "Action": ["iam:DeleteServiceLinkedRole"],
            "Resource": ["arn:aws:iam::*:role/aws-service-role/redshift.amazonaws.com/AWSServiceRoleForRedshift*"]
	 }
    ]
}

To delete a service-linked role by using the IAM console:

  1. Navigate to the IAM console and choose Roles from the navigation pane.

Screenshot of the Roles page in the IAM console

  1. Choose the service-linked role you want to delete and then choose Delete role. In this example, I choose the  AWSServiceRoleForRedshift service-linked role.

Screenshot of the AWSServiceRoleForRedshift service-linked role

  1. A dialog box asks you to confirm that you want to delete the service-linked role you have chosen. In the Last activity column, you can see when the AWS service last used the service-linked role, which tells you when the linked service last used the service-linked role to perform an action on your behalf. If you want to continue to delete the service-linked role, choose Yes, delete to delete the service-linked role.

Screenshot of the "Delete role" window

  1. IAM then checks whether you have any resources that require the service-linked role you are trying to delete. While IAM checks, you will see the status message, Deletion in progress, below the role name. Screenshot showing "Deletion in progress"
  1. If no resources require the service-linked role, IAM deletes the role from your account and displays a success message on the console.

Screenshot of the success message

  1. If there are AWS resources that require the service-linked role you are trying to delete, you will see the status message, Deletion failed, below the role name.

Screenshot showing the "Deletion failed"

  1. If you choose View details, you will see a message that explains the deletion failed because there are resources that use the service-linked role.
    Screenshot showing details about why the role deletion failed
  2. Choose View Resources to view the Amazon Resource Names (ARNs) of the first five resources that require the service-linked role. You can delete the service-linked role only after you delete all resources that require the service-linked role. In this example, only one resource requires the service-linked role.

Conclusion

Service-linked roles make it easier for you to delegate permissions to AWS services to create and manage AWS resources on your behalf and to understand all actions the service will perform on your behalf. If you no longer need to use an AWS service that uses a service-linked role, you can remove permissions from that service by deleting the service-linked role through the IAM console. However, before you delete a service-linked role, you must delete all the resources associated with that role to ensure that your resources remain in a consistent state.

If you have any questions, submit a comment in the “Comments” section below. If you need help working with service-linked roles, start a new thread on the IAM forum or contact AWS Support.

– Ujjwal

Greater Transparency into Actions AWS Services Perform on Your Behalf by Using AWS CloudTrail

Post Syndicated from Ujjwal Pugalia original https://aws.amazon.com/blogs/security/get-greater-transparency-into-actions-aws-services-perform-on-your-behalf-by-using-aws-cloudtrail/

To make managing your AWS account easier, some AWS services perform actions on your behalf, including the creation and management of AWS resources. For example, AWS Elastic Beanstalk automatically handles the deployment details of capacity provisioning, load balancing, auto-scaling, and application health monitoring. To make these AWS actions more transparent, AWS adds an AWS Identity and Access Management (IAM) service-linked roles to your account for each linked service you use. Service-linked roles let you view all actions an AWS service performs on your behalf by using AWS CloudTrail logs. This helps you monitor and audit the actions AWS services perform on your behalf. No additional actions are required from you and you can continue using AWS services the way you do today.

To learn more about which AWS services use service-linked roles and log actions on your behalf to CloudTrail, see AWS Services That Work with IAM. Over time, more AWS services will support service-linked roles. For more information about service-linked roles, see Role Terms and Concepts.

In this blog post, I demonstrate how to view CloudTrail logs so that you can more easily monitor and audit AWS services performing actions on your behalf. First, I show how AWS creates a service-linked role in your account automatically when you configure an AWS service that supports service-linked roles. Next, I show how you can view the policies of a service-linked role that grants an AWS service permission to perform actions on your behalf. Finally, I  use the configured AWS service to perform an action and show you how the action appears in your CloudTrail logs.

How AWS creates a service-linked role in your account automatically

I will use Amazon Lex as the AWS service that performs actions on your behalf for this post. You can use Amazon Lex to create chatbots that allow for highly engaging conversational experiences through voice and text. You also can use chatbots on mobile devices, web browsers, and popular chat platform channels such as Slack. Amazon Lex uses Amazon Polly on your behalf to synthesize speech that sounds like a human voice.

Amazon Lex uses two IAM service-linked roles:

  • AWSServiceRoleForLexBots — Amazon Lex uses this service-linked role to invoke Amazon Polly to synthesize speech responses for your chatbot.
  • AWSServiceRoleForLexChannels — Amazon Lex uses this service-linked role to post text to your chatbot when managing channels such as Slack.

You don’t need to create either of these roles manually. When you create your first chatbot using the Amazon Lex console, Amazon Lex creates the AWSServiceRoleForLexBots role for you. When you first associate a chatbot with a messaging channel, Amazon Lex creates the AWSServiceRoleForLexChannels role in your account.

1. Start configuring the AWS service that supports service-linked roles

Navigate to the Amazon Lex console, and choose Get Started to navigate to the Create your Lex bot page. For this example, I choose a sample chatbot called OrderFlowers. To learn how to create a custom chatbot, see Create a Custom Amazon Lex Bot.

Screenshot of making the choice to create an OrderFlowers chatbot

2. Complete the configuration for the AWS service

When you scroll down, you will see the settings for the OrderFlowers chatbot. Notice the field for the IAM role with the value, AWSServiceRoleForLexBots. This service-linked role is “Automatically created on your behalf.” After you have entered all details, choose Create to build your sample chatbot.

Screenshot of the automatically created service-linked role

AWS has created the AWSServiceRoleForLexBots service-linked role in your account. I will return to using the chatbot later in this post when I discuss how Amazon Lex performs actions on your behalf and how CloudTrail logs these actions. First, I will show how you can view the permissions for the AWSServiceRoleForLexBots service-linked role by using the IAM console.

How to view actions in the IAM console that AWS services perform on your behalf

When you configure an AWS service that supports service-linked roles, AWS creates a service-linked role in your account automatically. You can view the service-linked role by using the IAM console.

1. View the AWSServiceRoleForLexBots service-linked role on the IAM console

Go to the IAM console, and choose AWSServiceRoleForLexBots on the Roles page. You can confirm that this role is a service-linked role by viewing the Trusted entities column.

Screenshot of the service-linked role

2.View the trusted entities that can assume the AWSServiceRoleForLexBots service-linked role

Choose the Trust relationships tab on the AWSServiceRoleForLexBots role page. You can view the trusted entities that can assume the AWSServiceRoleForLexBots service-linked role to perform actions on your behalf. In this example, the trusted entity is lex.amazonaws.com.

Screenshot of the trusted entities that can assume the service-linked role

3. View the policy attached to the AWSServiceRoleForLexBots service-linked role

Choose AmazonLexBotPolicy on the Permissions tab to view the policy attached to the AWSServiceRoleForLexBots service-linked role. You can view the policy summary to see that AmazonLexBotPolicy grants permission to Amazon Lex to use Amazon Polly.

Screenshot showing that AmazonLexBotPolicy grants permission to Amazon Lex to use Amazon Polly

4. View the actions that the service-linked role grants permissions to use

Choose Polly to view the action, SynthesizeSpeech, that the AmazonLexBotPolicy grants permission to Amazon Lex to perform on your behalf. Amazon Lex uses this permission to synthesize speech responses for your chatbot. I show later in this post how you can monitor this SynthesizeSpeech action in your CloudTrail logs.

Screenshot showing the the action, SynthesizeSpeech, that the AmazonLexBotPolicy grants permission to Amazon Lex to perform on your behalf

Now that I know the trusted entity and the policy attached to the service-linked role, let’s go back to the chatbot I created earlier and see how CloudTrail logs the actions that Amazon Lex performs on my behalf.

How to use CloudTrail to view actions that AWS services perform on your behalf

As discussed already, I created an OrderFlowers chatbot on the Amazon Lex console. I will use the chatbot and display how the AWSServiceRoleForLexBots service-linked role helps me track actions in CloudTrail. First, though, I must have an active CloudTrail trail created that stores the logs in an Amazon S3 bucket. I will use a trail called TestTrail and an S3 bucket called account-ids-slr.

1. Use the Amazon Lex chatbot via the Amazon Lex console

In Step 2 in the first section of this post, when I chose Create, Amazon Lex built the OrderFlowers chatbot. After the chatbot was built, the right pane showed that a Test Bot was created. Now, I choose the microphone symbol in the right pane and provide voice input to test the OrderFlowers chatbot. In this example, I tell the chatbot, “I would like to order some flowers.” The bot replies to me by asking, “What type of flowers would you like to order?”

Screenshot of voice input to test the OrderFlowers chatbot

When the chatbot replies using voice, Amazon Lex uses Amazon Polly to synthesize speech from text to voice. Amazon Lex assumes the AWSServiceRoleForLexBots service-linked role to perform the SynthesizeSpeech action.

2. Check CloudTrail to view actions performed on your behalf

Now that I have created the chatbot, let’s see which actions were logged in CloudTrail. Choose CloudTrail from the Services drop-down menu to reach the CloudTrail console. Choose Trails and choose the S3 bucket in which you are storing your CloudTrail logs.

Screenshot of the TestTrail trail

In the S3 bucket, you will find log entries for the SynthesizeSpeech event. This means that CloudTrail logged the action when Amazon Lex assumed the AWSServiceRoleForLexBots service-linked role to invoke Amazon Polly to synthesize speech responses for your chatbot. You can monitor and audit this invocation, and it provides you with transparency into Amazon Polly’s SynthesizeSpeech action that Amazon Lex invoked on your behalf. The applicable CloudTrail log section follows and I have emphasized the key lines.

{  
         "eventVersion":"1.05",
         "userIdentity":{  
           "type":"AssumedRole",
            "principalId":"{principal-id}:OrderFlowers",
            "arn":"arn:aws:sts::{account-id}:assumed-role/AWSServiceRoleForLexBots/OrderFlowers",
            "accountId":"{account-id}",
            "accessKeyId":"{access-key-id}",
            "sessionContext":{  
               "attributes":{  
                  "mfaAuthenticated":"false",
                  "creationDate":"2017-09-17T17:30:05Z"
               },
               "sessionIssuer":{  
                  "type":"Role",
                  "principalId":"{principal-id}",
                  "arn":"arn:aws:iam:: {account-id}:role/aws-service-role/lex.amazonaws.com/AWSServiceRoleForLexBots",
                  "accountId":"{account-id",
                  "userName":"AWSServiceRoleForLexBots"
               }
            },
            "invokedBy":"lex.amazonaws.com"
         },
         "eventTime":"2017-09-17T17:30:05Z",
         "eventSource":"polly.amazonaws.com",
         "eventName":"SynthesizeSpeech",
         "awsRegion":"us-east-1",
         "sourceIPAddress":"lex.amazonaws.com",
         "userAgent":"lex.amazonaws.com",
         "requestParameters":{  
            "outputFormat":"mp3",
            "textType":"text",
            "voiceId":"Salli",
            "text":"**********"
         },
         "responseElements":{  
            "requestCharacters":45,
            "contentType":"audio/mpeg"
         },
         "requestID":"{request-id}",
         "eventID":"{event-id}",
         "eventType":"AwsApiCall",
         "recipientAccountId":"{account-id}"
      }

Conclusion

Service-linked roles make it easier for you to track and view actions that linked AWS services perform on your behalf by using CloudTrail. When an AWS service supports service-linked roles to enable this additional logging, you will see a service-linked role added to your account.

If you have comments about this post, submit a comment in the “Comments” section below. If you have questions about working with service-linked roles, start a new thread on the IAM forum or contact AWS Support.

– Ujjwal

Introducing an Easier Way to Delegate Permissions to AWS Services: Service-Linked Roles

Post Syndicated from Abhishek Pandey original https://aws.amazon.com/blogs/security/introducing-an-easier-way-to-delegate-permissions-to-aws-services-service-linked-roles/

Some AWS services create and manage AWS resources on your behalf. To do this, these services require you to delegate permissions to them by using AWS Identity and Access Management (IAM) roles. Today, AWS IAM introduces service-linked roles, which give you an easier and more secure way to delegate permissions to AWS services. To start, you can use service-linked roles with Amazon Lex, a service that enables you to build conversational interfaces in any application by using voice and text. Over time, more AWS services will use service-linked roles as a way for you to delegate permissions to them to create and manage AWS resources on your behalf. In this blog post, I walk through the details of service-linked roles and show how to use them.

Creation and management of service-linked roles

Each service-linked role links to an AWS service, which is called the linked service. Service-linked roles provide a secure way to delegate permissions to AWS services because only the linked service can assume a service-linked role. Additionally, AWS automatically defines and sets the permissions of service-linked roles, depending on the actions that the linked service performs on your behalf. This makes it easier for you to manage the permissions you delegate to AWS services. AWS allows only those changes to service-linked roles that do not remove the permissions required by the linked service to manage your resources, preventing you from making any changes that would leave your AWS resources in an inconsistent state. Service-linked roles also help you meet your monitoring and auditing requirements because all actions performed on your behalf by an AWS service using a service-linked role appear in your AWS CloudTrail logs.

When you work with an AWS service that uses service-linked roles, the service automatically creates a service-linked role for you. After that, whenever the service must act on your behalf to manage your resources, it assumes the service-linked role. You can view the details of the service-linked roles in your account by using the IAM console, IAM APIs, or the AWS CLI.

Service-linked roles follow a specific naming convention that includes a mandatory prefix that is defined by AWS and an optional suffix defined by you. The examples in the following table show how the role names of service-linked roles may appear.

Service-linked role namePrefixOptional suffix
AWSServiceRoleForLexBotsAWSServiceRoleForLexBotsNot set
AWSServiceRoleForElasticBeanstalk_myRoleAWSServiceRoleForElasticBeanstalkmyRole

If you are the administrator of your account and you do not want to grant permissions to other users to create roles or delegate permissions to AWS services, you can create service-linked roles for users in your account by using the IAM console, IAM APIs, or the AWS CLI. For more information about how to create service-linked roles through IAM, see the IAM documentation about creating a role to delegate permissions to an AWS service.

To create a service-linked role or to enable an AWS service to create one on your behalf, you must have permission for the iam:CreateServiceLinkedRole action. The following IAM policy grants the permission to create service-linked roles for Amazon Lex.

{ 
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "AllowCreationOfServiceLinkedRoleForLex",
            "Effect": "Allow",
            "Action": ["iam:CreateServiceLinkedRole"],
            "Resource": ["arn:aws:iam::*:role/aws-service-role/lex.amazonaws.com/AWSServiceRoleForLex*"],
	    "Condition": {
	         "StringLike":{
			"iam:AWSServiceName": "lex.amazonaws.com"
		  }
 	    }
        }
    ]
}

The preceding policy allows the iam:CreateServiceLinkedRole action when the linked service is Amazon Lex, and the name of the service-linked role starts with AWSServiceRoleForLex. For more information, see Working with Policies.

If you no longer wish to use a specific AWS service, you can revoke permissions for that service by deleting the service-linked role. You can do this from the linked service, and the service might require you to delete the resources that depend on the service-linked role. This helps ensure that you do not inadvertently delete a role that is required for your AWS resources to function properly. To learn more about how to delete a service-linked role, see the linked service’s documentation.

Permissions of service-linked roles

Just like existing IAM roles, the permissions of service-linked roles come from two policies: a permission policy and a trust policy. The permission policy determines what the role can and cannot do, and the trust policy defines who can assume the role. AWS automatically sets the permission and trust policies of service-linked roles.

For the permission policy, service-linked roles use an AWS managed policy. This means that when a service adds a new feature, AWS automatically updates the managed policy to enable the new functionality without requiring you to change the policy. In most cases, you do not have to update the permission policy of a service-linked role. However, some services may require you to add specific permissions to the role such as access to a specific Amazon S3 bucket. To learn more about how to add permissions if a service requires specific permissions, see the linked service’s documentation.

Only the linked AWS service can assume a service-linked role, which is why you cannot modify the trust policy of a service-linked role. You can allow your users to create service-linked roles for AWS services while not permitting them to escalate their own privileges. For example, imagine Alice is a developer on your team and she wants to delegate permissions to Amazon Lex. When Alice creates a service-linked role for Amazon Lex, AWS automatically attaches the permission and trust policies. The permission policy includes only the permissions that Amazon Lex needs to manage your resources (this best practice is known as least privilege), and the trust policy defines Amazon Lex as the trusted entity. As a result, Alice is able to create a service-linked role to delegate permissions to Amazon Lex. However, she is unable to edit the trust policy to include additional trusted entities. This prevents her from granting unapproved access to other users or escalating her own privileges, while still having the necessary permissions to create service-linked roles for Amazon Lex.

How to create a service-linked role by using the IAM console

The following steps lead you through creating a service-linked role by using the IAM console. However, before you create a service-linked role, make sure you have the right permissions to do so.

To create a service-linked role by using the IAM console:

  1. Navigate to the IAM console and choose Roles in the navigation pane.
    Screenshot of the IAM console
  2. Choose Create new role.
    Screenshot showing the "Create new role" button
  3. On the Select role type page, in the AWS service-linked role section, choose the AWS service for which you want to create the role. For this example, I choose Amazon Lex – Bots.
    Screenshot of choosing "Amazon Lex - Bots"
  4. Notice that the role name prefix is automatically populated. Type the role name suffix for the service-linked role. Some AWS services, such as Amazon Lex, do not support custom suffixes, in which case you should leave the role name suffix box blank.
    Screenshot of the role name suffix box
  5. Include a description of the new role. Notice that IAM automatically suggests a description for this role, which you can edit. For this example, I keep the suggested description.
    Screenshot of the "Role description" box
  6. Choose Create role. After the role is created, you can view it in the IAM console. Service-linked roles are marked with a cube-shaped icon in the console to help you distinguish these roles from other roles in your account.

Conclusion

With service-linked roles, delegating permissions to AWS services is easier because when you work with an AWS service that uses these roles, the service creates the role for you. You do not have to create IAM policies for delegating permissions to AWS services. Any changes to these roles that might interfere with your AWS resources do not go through. Delegation of permissions is secure because only the linked service is able to use these roles.

To see which AWS services support service-linked roles, see AWS services that work with IAM. If you have any comments about service-linked roles, submit a comment in the “Comments” section below. If you have questions about working with service-linked roles, please start a new thread on the IAM forum.

– Abhishek