Introduction
Today’s businesses depend more heavily than ever on applications and data analytics. The more an organization transitions its processes to digital systems, the more data it can take advantage of. Enterprise cloud platforms support these applications, with Amazon Web Services (AWS) being one of the most popular options.
As of 2023, Amazon reports that millions of customers use AWS (AWS, 2023). While AWS provides a powerful and cost-effective platform for organizations, it also introduces security challenges. Traditional cybersecurity methods, such as firewalls and VPNs (Virtual Private Networks), are not suited for protecting cloud platforms in the ways web pentesting might. Securing sensitive corporate data and custom applications on AWS requires a modern approach: AWS penetration testing. This guide explores AWS pentesting and the tools needed to perform it effectively.
A Deep-Dive into AWS Penetration Testing
AWS penetration testing, like other forms of pentesting, involves deliberate and controlled attempts to exploit vulnerabilities and identify attack vectors within a platform or system. Many organizations utilize in penetration testing and ethical hacking exercises to identify vulnerabilities before malicious actors are able to exploit them. However, pentesting in the cloud presents additional complexities.
What sets AWS pentesting apart from traditional pentesting is its alignment with Amazon’s shared responsibility model. AWS penetration testers must assess security risks to establish whether the responsibility lies with Amazon or the customer. Because penetration testing activities can mimic malicious attacks, many common pentesting practices are restricted on the AWS platform.
Fortunately, Amazon supports security testing and permits a range of AWS security testing techniques. Most AWS pentests fall into one of two categories:
Cloud-native attacks: This involves testing the cloud platform’s native features. Examples include exploiting IAM (Identity and Access Management) misconfigurations, AWS Lambda function vulnerabilities, or targeting serverless applications.
Misconfigured resources: AWS resources such as Amazon S3 Buckets, EC2 Instances, KMS (Key Management Services), and AWS Config are valuable but can create security risks if misconfigured. Regular penetration testing of these configurations is essential.
Can We Perform Penetration Testing on AWS?
Given the challenges of the cloud and Amazon’s limitations, it could be called into question as to if penetration testing on AWS is possible. Yes, it is, but it requires a different approach than traditional pentesting. Allowed AWS pentesting practices include:
- Vulnerability scanning
- Web application scanning
- Port scanning
- Injections
- Exploiting found vulnerabilities
- Forgery
- Fuzzing
However, the following pentesting techniques are prohibited:
- DNS (Domain Name System) zone hijacking
- Denial of service (DoS) or distributed denial of service (DDoS) attacks
- Simulated DoS and DDoS attacks
- Port flooding
- Protocol flooding
- API request flooding
- Login/authentication request flooding
AWS penetration testing techniques that rely on brute force or methods resembling a DoS or DDoS attack are generally not permitted. Before conducting any AWS security testing, ensure it complies with Amazon’s terms of service.
Despite the limitations and challenges associated with AWS security testing, it remains crucial for organizations using the platform. A security breach can result in severe consequences, including severe financial loss per incident. Given the risks, AWS pentesting is one of the most vital cybersecurity defenses available.
AWS pentesting helps identify security flaws that might otherwise go unnoticed until a malicious actor exploits them. Most businesses today have legal or regulatory obligations to secure employee and customer data. Penetration testing aids in protecting this sensitive information while providing evidence of compliance with laws and regulations.
Prerequisites to an AWS Penetration Test
Before getting started with AWS pentesting, complete the following prerequisites:
Understand Amazon’s shared responsibility model: Understand the shared responsibility guidelines. Amazon secures the infrastructure powering AWS services, while customers are responsible for the security of guest operating systems and applications within their AWS environment.
Secure your AWS environment: Apply any pending security updates to Linux or Windows VMs hosted on AWS, as well as the underlying applications. Properly configure the AWS firewall and implement other AWS security measures typical of a live production environment.
Develop a plan: List AWS instances and applications that’re being tested. Identify the services exposed to the public internet and develop a testing plan that thoroughly examines the security of those services or applications.
After completing these prerequisites, follow these steps, which are comparable to traditional pentesting methods:
Get authorization: Obtain appropriate approval from the AWS account owner and, if applicable, the application administrator before conducting penetration tests.
Define your goals: Identify the target system and AWS service to be tested. Specify the expected results and any potential anomalies.
Map the attack surface: Identify AWS services, instances, network subnets, S3 buckets, IAM roles, and other relevant services to test.
Perform the vulnerability assessment: Use AWS pentesting tools to search for vulnerabilities such as Nikto, Nmap, CloudMapper, PacBot, AWS Trusted Advisor, etc.
Exploit the vulnerabilities: If a vulnerability is found, attempt to exploit it and document any results.
Report your findings: Draft a report detailing the findings of your AWS penetration testing session, including any remediation recommendations.
AWS Penetration Testing VS Traditional Penetration Testing
Traditional Penetration Testing
Traditional penetration testing often targets physical infrastructure, such as on-premises servers and networks. Planning and executing traditional pentesting is usually more straightforward because the organization’s IT team fully owns and controls the systems and networks being tested. Obtaining permission for pentesting is simple, as all system administrators are aware of the activities. Testers, either part of the IT team or granted access, are free to perform tests without the restrictions imposed by cloud providers.
AWS Penetration Testing
In contrast, AWS penetration testing focuses on cloud services, containers, server-less applications, and other cloud technologies. AWS pentesting offers key advantages like suitability for automation and scalability. AWS environments provide multiple opportunities for automation, making pentesting more efficient compared to the typically manual processes of traditional pentesting. Additionally, the scale-able nature of the cloud makes it easier to conduct pentesting on large platforms within AWS compared to traditional infrastructure.
Some Common Tools Used in AWS Penetration Tests
The limitations of AWS pentesting mean you won’t be able to use many common pentesting tools. However, Amazon offers several applications that function as AWS pentesting tools, including:
AWS Command Line Interface (CLI): The AWS CLI is a standard tool for all customers and users, allowing testers to interact with AWS services programmatically. It can be used for tasks such as resource enumeration, security group analysis, and credential management.
AWS Identity and Access Management (IAM) Policy Simulator: This built-in AWS tool helps testers simulate IAM policy changes and evaluate their impact on AWS resources. It is valuable for understanding the potential consequences of policy modifications.
AWS Config: AWS Config provides a detailed inventory of AWS resources and their configurations, helping testers assess the security posture of AWS resources by identifying deviations from desired configurations.
AWS Security Hub: The AWS Security Hub offers a centralized view of security alerts and compliance status across AWS accounts. It aggregates findings from various AWS security services and third-party tools, making it easier to identify and prioritize security issues.
AWS GuardDuty: GuardDuty is a paid add-on that provides managed threat detection services. It continuously monitors AWS accounts for malicious activity and unauthorized access, generating alerts based on AWS CloudTrail logs and VPC (Virtual Private Cloud) Flow Logs analysis.
These AWS tools facilitate effective penetration testing within the platform’s limitations, helping ensure robust security for cloud-based resources.
Common Strategies Used in AWS Penetration Tests
Following reconnaissance, the next steps will be to identify attack vectors in the documented information and use it to craft effective attack vectors.
Exploiting Misconfigured S3 Buckets: Searching for S3 buckets with improper permissions to access, modify, or delete sensitive data. Attackers typically use automated tools to scan for publicly accessible buckets.
IAM Role Exploitation: Identifying and exploiting overly permissive IAM roles and policies. This can involve escalating privileges or assuming roles with higher access levels. Attackers may also exploit unused or default IAM roles.
Credential Theft and Abuse: Obtaining AWS access keys and secret keys through phishing, social engineering, or exploiting mismanaged credentials in code repos like Github. This is a very common and often rewarding strategy. Once obtained, these credentials can be used to access AWS resources.
API Attacks: Targeting insecure or improperly authenticated APIs to perform injection attacks, data exfiltration, or unauthorized operations. Attackers often look for endpoints that lack proper security controls.
Lambda Function Exploitation: Exploiting vulnerabilities in serverless applications, such as insecure code, improper handling of environment variables, or excessive permissions granted to Lambda functions.
EC2 Instance Attacks: Exploiting unpatched software, weak SSH keys, or default security group settings on EC2 instances. Attackers might also look for exposed management interfaces or services.
Privilege Escalation: Exploiting vulnerabilities or misconfigurations to gain higher levels of access within the AWS environment. This can involve leveraging IAM roles, policies, or exploiting software vulnerabilities.
Network Attacks: Targeting network configurations such as security groups, VPCs (Virtual Private Clouds), and ELBs (Elastic Load Balancers). Attackers might attempt to bypass security controls or access internal services.
Data Exfiltration: Using compromised credentials or misconfigured services to steal sensitive data from databases, storage services, or other AWS resources. This can involve exporting data to external locations.
Denial of Service (DoS): Attempting to disrupt AWS services by overwhelming them with traffic or exploiting resource limits. While traditional DoS attacks are generally not allowed in pentesting, understanding potential DoS vulnerabilities is still important.
Persistence Mechanisms: Establishing a foothold within the AWS environment to maintain long-term access. This might involve creating backdoor IAM roles, setting up rogue instances, or modifying CloudFormation templates.
By employing these strategies, attackers can identify and exploit weaknesses in AWS environments, highlighting the importance of robust security practices and regular penetration testing.