Category: Security


Reset Your AWS Root Account’s Lost MFA Device Faster by Using the AWS Management Console

To help secure your AWS resources, AWS recommends that you follow the AWS Identity and Access Management (IAM) best practice of enabling multi-factor authentication (MFA) for the root user of your account. With MFA turned on, the root user of your account is required to submit one form of authentication, which is the account password, and another form of authentication, such as a one-time password (OTP) from an MFA device. If you have MFA enabled on your root account and you lose or misplace your root MFA device, you can now reset it by using the AWS Management Console.

Now, your root user can use the AWS sign-in page to verify your root account’s email address and phone number. Then, the root user can deactivate the lost MFA device and set up a new MFA device in its place. Note that this information verification feature is available only for AWS root users with a phone number associated with their root account. If your root user does not have a valid phone number associated with your root account, the root user must call AWS Support to reset the lost MFA device.

In this blog post, I demonstrate how to reset a lost MFA device faster by using the AWS Management Console to verify your root user’s email address and phone number. I then demonstrate how to set up a virtual MFA device that you can use in place of the lost MFA device.

Note: This feature is available only to AWS accounts created before September 14, 2017. If you created your account after September 14, 2017, contact AWS Support to reset your lost MFA device.

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How to Enable Your Users to Access Office 365 with AWS Microsoft Active Directory Credentials

You can now enable your users to access Microsoft Office 365 with credentials that you manage in AWS Directory Service for Microsoft Active Directory, also known as AWS Microsoft AD. You can accomplish this by deploying Microsoft Azure Active Directory (AD) Connect and Active Directory Federation Services for Windows Server 2016 (AD FS 2016) with AWS Microsoft AD. AWS Microsoft AD makes it possible and easy for you to build a Windows environment in the AWS Cloud, synchronize your AWS Microsoft AD users into Microsoft Azure AD, and use Office 365, all without needing to create and manage AD domain controllers. Now you can also benefit from the broad set of AWS Cloud services for compute, storage, database, and Internet of Things (IoT) while continuing to use Office 365 business productivity apps—all with a single AD domain.

Office 365 provides different options to support user authentication with identities that come from AD. One common way to do this is to use Azure AD Connect and AD FS together with your AD directory. In this model, you use Azure AD Connect to synchronize user names from AD into Azure AD so that Office 365 can use those identities. To complete this solution, you use AD FS to enable Office 365 to authenticate the identities against your AD directory. Good news: AWS Microsoft AD now supports this model!

In this blog post, we show how to use Azure AD Connect and AD FS with AWS Microsoft AD so that your employees can access Office 365 by using their AD credentials. (more…)

Now Available: Improvements to How You Sign In to Your AWS Account

Today, AWS made improvements to the way you sign in to your AWS account. Whether you sign in as your account’s root user or an AWS Identity and Access Management (IAM) user, you can now sign in from the AWS Management Console’s homepage. This means that if you sign in as an IAM user, you no longer have to use an account-specific URL. However, the account-specific URL you have used in the past to sign in will continue to work.

In the new sign-in experience, you can sign in from the home page using either your root user’s or IAM user’s credentials. In the first step, root users enter their email address; IAM users enter their account ID (or account alias). In the second step, root users enter their password; IAM users enter their user name and password.

In this blog post, I explain the improvements to the way you sign in to your AWS account as a root user or IAM user. If you use a password manager to help you sign in to your account, you may need to make updates so that it will work with the new sign-in experience. (more…)

AWS Encryption SDK: How to Decide if Data Key Caching Is Right for Your Application

AWS KMS image

Today, the AWS Crypto Tools team introduced a new feature in the AWS Encryption SDK: data key caching. Data key caching lets you reuse the data keys that protect your data, instead of generating a new data key for each encryption operation.

Data key caching can reduce latency, improve throughput, reduce cost, and help you stay within service limits as your application scales. In particular, caching might help if your application is hitting the AWS Key Management Service (KMS) requests-per-second limit and raising the limit does not solve the problem.

However, these benefits come with some security tradeoffs. Encryption best practices generally discourage extensive reuse of data keys.

In this blog post, I explore those tradeoffs and provide information that can help you decide whether data key caching is a good strategy for your application. I also explain how data key caching is implemented in the AWS Encryption SDK and describe the security thresholds that you can set to limit the reuse of data keys. Finally, I provide some practical examples of using the security thresholds to meet cost, performance, and security goals.

Introducing data key caching

The AWS Encryption SDK is a client-side encryption library that makes it easier for you to implement cryptography best practices in your application. It includes secure default behavior for developers who are not encryption experts, while being flexible enough to work for the most experienced users. (more…)

Newly Updated: Example AWS IAM Policies for You to Use and Customize

To help you grant access to specific resources and conditions, the Example Policies page in the AWS Identity and Access Management (IAM) documentation now includes more than thirty policies for you to use or customize to meet your permissions requirements. The AWS Support team developed these policies from their experiences working with AWS customers over the years. The example policies cover common permissions use cases you might encounter across services such as Amazon DynamoDB, Amazon EC2, AWS Elastic Beanstalk, Amazon RDS, Amazon S3, and IAM.

In this blog post, I introduce the updated Example Policies page and explain how to use and customize these policies for your needs.

The new Example Policies page

The Example Policies page in the IAM User Guide now provides an overview of the example policies and includes a link to view each policy on a separate page. Note that each of these policies has been reviewed and approved by AWS Support. If you would like to submit a policy that you have found to be particularly useful, post it on the IAM forum. (more…)

How to Monitor and Visualize Failed SSH Access Attempts to Amazon EC2 Linux Instances

As part of the AWS Shared Responsibility Model, you are responsible for monitoring and managing your resources at the operating system and application level. When you monitor your application servers, for example, you can measure, visualize, react to, and improve the security of those servers. You probably already do this on premises or in other environments, and you can adapt your existing processes, tools, and methodologies for use in the AWS Cloud. For more details about best practices for monitoring your AWS resources, see the “Manage Security Monitoring, Alerting, Audit Trail, and Incident Response” section in the AWS Security Best Practices whitepaper.

This blog post focuses on how to log and create alarms on invalid Secure Shell (SSH) access attempts. Implementing live monitoring and session recording facilitates the identification of unauthorized activity and can help confirm that remote users access only those systems they are authorized to use. With SSH log information in hand (such as invalid access type, bad private keys, and remote IP addresses), you can take proactive actions to protect your servers. For example, you can use an AWS Lambda function to adjust your server’s security rules when an alarm is triggered that indicates an invalid SSH access attempt.

In this post, I demonstrate how to use Amazon CloudWatch Logs to monitor SSH access to your application servers (Amazon EC2 Linux instances) so that you can monitor rejected SSH connection requests and take action. I also show how to configure CloudWatch Logs to send SSH access logs from application servers that reside in a public subnet. Last, I demonstrate how to visualize how many attempts are made to SSH into your application servers with bad private keys and invalid user names. Using these techniques and tools can help you improve the security of your application servers.

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How to Use AWS Organizations to Automate End-to-End Account Creation

AWS Organizations offers new capabilities for managing AWS accounts, including automated account creation via the Organizations API. For example, you can bring new development teams onboard by using the Organizations API to create an account, AWS CloudFormation templates to configure the account (such as for AWS Identity and Access Management [IAM] and networking), and service control policies (SCPs) to help enforce corporate policies.

In this blog post, I demonstrate the step-by-step process for end-to-end account creation in Organizations as well as how to automate the entire process. I also show how to move a new account into an organizational unit (OU).

Process overview

The following process flow diagram illustrates the steps required to create an account, configure the account, and then move it into an OU so that the account can take advantage of the centralized SCP functionality in Organizations. The tasks in the blue nodes occur in the master account in the organization in question, and the task in the orange node occurs in the new member account I create. In this post, I provide a script (in both Bash/CLI and Python) that you can use to automate this account creation process, and I walk through each step shown in the diagram to explain the process in detail. For the purposes of this post, I use the AWS CLI in combination with CloudFormation to create and configure an account. (more…)

AWS Adds 12 More Services to Its PCI DSS Compliance Program

Twelve more AWS services have obtained Payment Card Industry Data Security Standard (PCI DSS) compliance, giving you more options, flexibility, and functionality to process and store sensitive payment card data in the AWS Cloud. The services were audited by Coalfire to ensure that they meet strict PCI DSS standards.

The newly compliant AWS services are:

AWS now offers 42 services that meet PCI DSS standards, putting administrators in better control of their frameworks and making workloads more efficient and cost effective.

For more information about the AWS PCI DSS compliance program, see Compliance Resources, AWS Services in Scope by Compliance Program, and PCI DSS Compliance.

– Sara

How to Configure Even Stronger Password Policies to Help Meet Your Security Standards by Using AWS Directory Service for Microsoft Active Directory

With AWS Directory Service for Microsoft Active Directory (Enterprise Edition), also known as AWS Microsoft AD, you can now create and enforce custom password policies for your Microsoft Windows users. AWS Microsoft AD now includes five empty password policies that you can edit and apply with standard Microsoft password policy tools such as Active Directory Administrative Center (ADAC). With this capability, you are no longer limited to the default Windows password policy. Now, you can configure even stronger password policies and define lockout policies that specify when to lock out an account after login failures.

In this blog post, I demonstrate how to edit these new password policies to help you meet your security standards by using AWS Microsoft AD. I also introduce the password attributes you can modify and demonstrate how to apply password policies to user groups in your domain. (more…)

How to Increase the Redundancy and Performance of Your AWS Directory Service for Microsoft AD Directory by Adding Domain Controllers

You can now increase the redundancy and performance of your AWS Directory Service for Microsoft Active Directory (Enterprise Edition), also known as AWS Microsoft AD, directory by deploying additional domain controllers. Adding domain controllers increases redundancy, resulting in even greater resilience and higher availability. This new capability enables you to have at least two domain controllers operating, even if an Availability Zone were to be temporarily unavailable. The additional domain controllers also improve the performance of your applications by enabling directory clients to load-balance their requests across a larger number of domain controllers. For example, AWS Microsoft AD enables you to use larger fleets of Amazon EC2 instances to run .NET applications that perform frequent user attribute lookups.

AWS Microsoft AD is a highly available, managed Active Directory built on actual Microsoft Windows Server 2012 R2 in the AWS Cloud. When you create your AWS Microsoft AD directory, AWS deploys two domain controllers that are exclusively yours in separate Availability Zones for high availability. Now, you can deploy additional domain controllers easily via the Directory Service console or API, by specifying the total number of domain controllers that you want.

AWS Microsoft AD distributes the additional domain controllers across the Availability Zones and subnets within the Amazon VPC where your directory is running. AWS deploys the domain controllers, configures them to replicate directory changes, monitors for and repairs any issues, performs daily snapshots, and updates the domain controllers with patches. This reduces the effort and complexity of creating and managing your own domain controllers in the AWS Cloud.

In this blog post, I create an AWS Microsoft AD directory with two domain controllers in each Availability Zone. This ensures that I always have at least two domain controllers operating, even if an entire Availability Zone were to be temporarily unavailable. To accomplish this, first I create an AWS Microsoft AD directory with one domain controller per Availability Zone, and then I deploy one additional domain controller per Availability Zone.

Solution architecture

The following diagram shows how AWS Microsoft AD deploys all the domain controllers in this solution after you complete Steps 1 and 2. In Step 1, AWS Microsoft AD deploys the two required domain controllers across multiple Availability Zones and subnets in an Amazon VPC. In Step 2, AWS Microsoft AD deploys one additional domain controller per Availability Zone and subnet. (more…)