In recent years, cloud computing has become the backbone of modern IT infrastructure, offering scalability, flexibility, and cost-efficiency. However, this rapid adoption has also introduced new security challenges, particularly concerning the Instance Metadata Service (IMDS) used by cloud providers like Amazon Web Services (AWS). IMDS is a crucial component that provides information about running instances, including sensitive data such as security credentials. Unfortunately, vulnerabilities within IMDS have been exploited by malicious actors to gain unauthorized access to cloud environments, leading to significant security breaches.
Understanding the Instance Metadata Service (IMDS):
IMDS is an HTTP endpoint accessible from within a cloud instance, designed to provide metadata about the instance without requiring authentication. This metadata includes details like instance ID, AMI ID, and, critically, temporary security credentials associated with the instance’s Identity and Access Management (IAM) role. These credentials allow applications running on the instance to interact with other AWS services securely.
Exploitation Techniques:
Attackers have developed several methods to exploit IMDS vulnerabilities, primarily focusing on Server-Side Request Forgery (SSRF) attacks and misconfigurations:
1. SSRF Attacks:
SSRF vulnerabilities occur when a web application allows an attacker to manipulate server-side requests. By exploiting SSRF, attackers can send crafted requests to internal services, including IMDS. For instance, if a web application fails to validate user-supplied URLs properly, an attacker can trick the server into making a request to the IMDS endpoint (`http://169.254.169.254/latest/meta-data/iam/security-credentials/`). This request can return temporary IAM credentials, which the attacker can then use to access other AWS services.
In a notable campaign detected in March 2025, threat actors targeted websites hosted on Amazon EC2 instances by exploiting SSRF vulnerabilities. They sent HTTP GET requests to parameters like `url`, `dest`, `file`, `redirect`, `target`, and `uri` to trigger SSRF and access IMDS. This allowed them to retrieve IAM role credentials and escalate privileges within the victim’s environment. ([cybersecuritynews.com](https://cybersecuritynews.com/hackers-exploiting-ec2-instance-metadata-vulnerability/?utm_source=openai))
2. Misconfigured Access Controls:
Misconfigurations in access controls can inadvertently expose IMDS to unauthorized access. For example, if an application running on an EC2 instance has overly permissive network settings or lacks proper input validation, it may allow external entities to interact with IMDS. This exposure can lead to unauthorized retrieval of sensitive metadata and credentials.
In a large-scale attack observed in 2025, attackers exploited exposed environment variable files (`.env`) on misconfigured web applications. These files contained AWS IAM access keys, which the attackers used to create new IAM roles with elevated privileges, leading to data theft and ransom demands. ([cybersecuritynews.com](https://cybersecuritynews.com/aws-env-extortion-110k-domains/?utm_source=openai))
Case Studies:
1. Commvault Zero-Day Exploit:
In February 2025, Commvault, a data protection solutions provider, experienced a breach when attackers exploited a zero-day vulnerability (CVE-2025-3928) in their web server software. This flaw allowed remote authenticated attackers with low privileges to plant web shells on target servers. Although no backup data was compromised, the incident underscored the risks associated with vulnerabilities that can be exploited to access sensitive cloud environments. ([cybersecuritynews.com](https://cybersecuritynews.com/commvault-hackers-exploited-zero-day-vulnerability/?utm_source=openai))
2. Microsoft Copilot Studio Vulnerability:
Researchers discovered a critical SSRF vulnerability (CVE-2024-38206) in Microsoft’s Copilot Studio, an AI chatbot development tool. By leveraging this flaw, attackers could access Microsoft’s internal infrastructure, including IMDS and internal databases. This vulnerability highlighted the potential risks associated with AI-powered cloud services that can make external HTTP requests. ([cybersecuritynews.com](https://cybersecuritynews.com/microsoft-copilot-studio-exploited/?utm_source=openai))
Mitigation Strategies:
To protect cloud environments from IMDS exploitation, organizations should implement the following measures:
1. Transition to IMDSv2:
AWS introduced IMDSv2 to enhance security by requiring session tokens for metadata access, mitigating the risk of SSRF attacks. Organizations should configure their instances to use IMDSv2 exclusively.
2. Implement Strict Access Controls:
Ensure that applications have the minimum necessary permissions and that network access to IMDS is restricted. Use security groups and network ACLs to control traffic flow.
3. Regular Security Audits:
Conduct periodic reviews of cloud configurations, access controls, and application code to identify and remediate vulnerabilities.
4. Input Validation:
Implement robust input validation to prevent SSRF vulnerabilities. Ensure that user-supplied data is properly sanitized before being processed by the application.
5. Monitor and Log Access:
Enable detailed logging and monitoring of access to IMDS and other critical services. Use anomaly detection to identify suspicious activities.
Conclusion:
The exploitation of IMDS vulnerabilities poses a significant threat to cloud security. By understanding the mechanisms of these attacks and implementing robust security practices, organizations can safeguard their cloud environments against unauthorized access and potential data breaches.
