Top Nine Easy ways to secure AWS S3 buckets

AWS S3 buckets are one of the most-used AWS services out there due to their affordable price, their versatility, and their easy-to-use web interface. Despite how easy it is, and how often people mention how easy it is, ease also comes with security risks like unsecured AWS S3 buckets.

There have been several instances of high-profile breaches of data in S3 buckets. In one recent instance, researchers found misconfigured Amazon S3 buckets containing the data of more than 80 U.S. cities, mostly in New England.

Ethical Hackers at WizCase said the misconfigured S3 buckets contained more than 1.6 million files and 1,000 gigabytes of data. Local residents’ addresses, phone numbers, identification documents, and tax records were compromised. It was difficult to estimate how many residents were exposed due to the large number and variety of documents.

Organizations often leave S3 buckets open by mistake. S3 buckets run on AWS, so administrators assume that they are inherently secure. AWS offers a high level of security for its cloud services, but there are some steps you can take to help prevent attacks:

Tip 1: Secure Data Using AWS S3 Encryption

Security personnel should encrypt all data while it is in transit, that is traveling to and from S3, and while it is at rest on disk in S3 data centers. S3 encryption is easy to accomplish by using client-side encryption or by using Secure Socket Layer/Transport Layer Security (SSL/TLS).

To protect your data at rest, S3 offers the following two options:

Server-Side Encryption: AWS encrypts raw data as you send it, encrypts it and stores it on data centers. AWS decrypts it when you want it, and sends it back to you.
Client-Side Encryption: If you choose this encryption method instead of the default in AWS, you will encrypt the data before sending it to AWS, which then decrypts it once you get it back.
Are you interested in becoming a AWS cloud practitioner? 
Check out the Thinkcloudly AWS Cloud practitioner course today!

Tip 2: Block public access to AWS S3 buckets

New buckets, objects, and access points are by default not set up for public access. But it is possible to change these configurations to allow public access – meaning sensitive data can potentially be accessed by any user by visiting a website. Unless the company explicitly demands any member of the public to interact with a particular S3 bucket, make sure all buckets are not public.

To block public access, use the S3 Block Public Access settings to override S3 permissions and prevent accidental or intentional public exposure. With these settings, admins have full control, no matter how resources are created.

Tip 3: Using Access Control management

Amazon Web Services have AWS Identity and Access Management (IAM) policies in place that let you control authentication and authorization for your account.
You’ll need to ensure that any roles you define only have the access necessary to complete their jobs, reducing the risk of unauthorized use if one’s account is compromised. One example is that HR staff may be able to access reports on their recruitment figures but not reports on company expenditure.
Below are the different  ways to control access to your S3 buckets and resources:
  • Limit the IAM User Permissions:  A key service Identity and Access Management (IAM) enables is the principle of least privilege; if this is used to limit the amount of access and resource assignment you can ensure administrators have only the level of access they need to perform day-to-day operations and protect your data. This limits the chance of human error which is a common reason for misconfigured S3 buckets and, in turn, a leading cause of data leakage.
  • Use ACLs to control Access: Access control lists (ACLs) are one of the resource-based methods that you can use to manage access to your buckets and objects. ACLs allow you to grant basic read/write permissions to other AWS accounts. There are certain limits to what can be done by adjusting ACLs.

For example, you can grant permissions only to other AWS accounts, not to users within your account. While it is not possible to specify conditions under which someone is permitted to use a file, an ACL can be suitable for more specific instances. For example, if a bucket owner permits other AWS accounts to upload objects, they can only manage these objects’ permissions through object ACL if the account that owns the object is the one granting permissions.

  • Block Amazon S3 Public Access: Amazon provides a central method for restricting public access to your S3 data. You can override any bucket policies and object permissions if you use the Amazon S3 Block Public Access setting. Keep in mind that while block public settings can be used for buckets, AWS accounts, and wireless networks.
Become certified in the most popular cloud technology AWS!

Tip 4: Use S3 Lock

S3 Object Lock provides the WORM (write-once, read-many) security level. For example, when enabled, objects stored under the lock are protected from deletion or overwrite.

The AWS S3 object locking makes it challenging to delete data. Security risks to the data are seen primarily in two ways by stealing data and by deleting data or assets.
S3 Object Locking works in this way: Preventing the deletion of an object or object overwriting. It basically makes the S3 object immutable by offering the following two ways to manage object retention by choosing a retention period or putting a legal hold on it, it will not disappear.

Tip 5: Create Data copies

This is the most popular strategy because it guarantees the protection of data. You can back up and automate all backup processes through the AWS Backup service, which supports a variety of AWS services, including Amazon EFS, DynamoDB, RDS, EBS, and Storage Gateway.

Tip 6: Enforcing SSL

For increased security, using SSL is an excellent way to go when communicating with S3 buckets. That way, HTTP and HTTPs both might be enabled, preventing an attacker from listening in on your transmissions to the S3 server.

Tip 7: Multiple layers of security

If a layer of your security fails due to improper configuration, human error, or a sophisticated attack, then other protection layers may be the difference between a security breach and security.
One powerful tool is multi-factor authentication (AWS MFA). When paired with a password or other authentication methods, it adds a second layer of security. it is a qualification you must know- the first factor. To become an MFA holder, an additional requirement is having something distinct as the second factor. This could be in the form of a physical device, such as a Yubikey security key, or dynamically generated codes from an authentication application like Auth. OTP codes usually last for 30-60 seconds, then expire.
Employing both factors – username and password, for example – in authenticating a user or device creates dramatically increased security. Even if both factors are compromised, they are only valid for a few seconds.
For Amazon S3 buckets, AWS supports MFA Delete which requires two-factor authentication to alter the versioning state of your bucket or to permanently delete it. The MFA Delete setting can only be enabled by the owner of the bucket.

Tip 8: Use logs to enhance S3 security

Security breaches are not always sudden, but can be identified beforehand through either auditing or reviewing logs.
Amazon Web Services (AWS) has many tools to assist its customers. Amazon CloudWatch is one such tool for DevOps and IT managers. This is a service designed to give you a unified view of your Amazon Web Services and on-premises servers. With it, you can detect problems, visualize logs, and automate actions to remediate any issues that arise.

Tip 9: Enable S3 Versioning

With  S3 versioning enabled, Amazon Web Services can record multiple objects as it accepts requests for the same object, rather than storing just one object per request. For example, a request from 3 separate sources can result in 3 different stored versions of the same object.

AWS is really interesting and fruitfull to study. Explore our more services to give your knowledge a sharp edge.

Wrapping up:

In a nutshell  below are the ways to secure S3 buckets :

  • Configuration – Configure your security in accordance with your business needs
  • Encryption – Encrypt your data at rest
  • Role-based access -Using the least privileges and role-based access is a way to restrict access
  • Multi-factor authentication – Utilize multiple layers of security
  • Auditing and logging – detect and follow up on attacks
We hope you will benefit from the techniques and strategies described in this article by preventing mistakes with S3 buckets, protecting your IT workloads, and preventing data breaches.
Do you have an AWS interview coming up? 
Check out these recent AWS interview questions and answers.