Cloud metadata service attacks exploit the instance metadata endpoints (such as http://169.254.169.254) available within cloud compute instances to steal credentials, discover infrastructure details, and escalate privileges. The metadata service provides temporary credentials to instance roles, making it a high-value target for attackers who achieve any level of code execution on a cloud instance.
Cloud providers expose metadata services at well-known IP addresses accessible from within instances. AWS Instance Metadata Service (IMDS) at 169.254.169.254 provides IAM role credentials, instance identity documents, user data scripts (which may contain secrets), and network configuration. Attackers reach the metadata service through Server-Side Request Forgery (SSRF) vulnerabilities in web applications, command injection, or any code execution on the instance. The stolen IAM credentials can be used from any location until they expire. Similar services exist in Azure (169.254.169.254) and GCP (metadata.google.internal). The Capital One breach demonstrated the devastating impact when SSRF combined with overprivileged instance roles enabled access to over 100 million customer records.
Metadata service attacks are among the most impactful cloud-specific techniques because they convert web application vulnerabilities into cloud infrastructure compromise. A simple SSRF vulnerability that would have limited impact in traditional infrastructure becomes a path to full cloud account access when the target instance has a privileged IAM role. IMDSv2 in AWS mitigates many attack patterns but requires explicit adoption.
CDA covers metadata service attacks within the VSD and IAT domains as a critical cloud security topic. Theater missions include SSRF-to-metadata exploitation scenarios. Our approach emphasizes enforcing IMDSv2, minimizing instance role permissions, and treating metadata service access as a high-severity finding.