Description

Improper neutralization of special elements used in a template engine in the CDK generator in Amazon awslabs.dynamodb-mcp-server before 2.1.6 might allow a context-dependent actor to execute arbitrary code on the host that deploys the generated application via crafted table, index, or attribute names in a data model file.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-09-04T18:18:05.977Z",
  "pubdate": "2026-09-04T18:18:05.977Z",
  "executiveSummary": "The vulnerability involves improper neutralization of special elements within the template engine utilized by the CDK generator in the awslabs.dynamodb-mcp-server project.\nThis flaw allows a context-dependent attacker to achieve remote code execution (RCE) on the host system responsible for deploying the generated AWS CDK application.\nThe vulnerability affects all versions of the product prior to 2.1.6.\nThe attack vector relies on supplying maliciously crafted metadata—specifically table, index, or attribute names—within the data model file processed by the generator.\nThe primary risk is a total compromise of the deployment host, as the template engine fails to sanitize user-provided identifiers before incorporating them into the generated infrastructure-as-code output.\nExploitation requires an attacker to have control over or the ability to influence the data model configuration file used as input for the server's code generation process.\nSuccessful execution grants the attacker the execution context of the underlying deployment environment, leading to potential privilege escalation or lateral movement within the CI/CD pipeline or developer workstation.",
  "technicalDetails": "The root cause of this vulnerability lies in an injection flaw within the template engine implementation of the awslabs.dynamodb-mcp-server CDK generator. The generator parses user-defined schemas to produce AWS Cloud Development Kit (CDK) constructs. When these schemas contain maliciously crafted strings in fields designated for table, index, or attribute names, the template engine fails to properly escape or neutralize special characters.\nIn template-driven code generation, identifiers are often directly interpolated into code blocks. If the engine treats the input as executable code or metadata that influences the code structure (e.g., template directives), an attacker can inject arbitrary template expressions. This bypasses the intended safe construction of the IaC code, enabling the execution of arbitrary commands during the generation or subsequent deployment phase.\nThe attack flow begins when an attacker provides a crafted data model file to the dynamodb-mcp-server. The server processes this model to generate CDK artifacts. During the parsing stage, the template engine interprets the malicious input characters as control sequences rather than literal string data. As the template engine resolves these sequences, it executes payloads injected by the attacker. Because the generator typically operates within the context of the user's build environment or server-side deployment tool, the resulting execution inherits the privileges of that process.\nThis vulnerability is particularly critical for server-side deployments where the tool might be invoked on behalf of multiple users or integrated into automated pipeline systems. If an attacker influences the input schema, they can force the host machine to execute arbitrary shell commands or malicious scripts upon generation. This post-exploitation impact includes full system compromise, exfiltration of environment variables—such as sensitive AWS credentials—and the ability to alter the generated infrastructure to create backdoors in the target AWS environment.\nThe vulnerability exists in all versions before 2.1.6. There are no specific authentication or privilege requirements to trigger the vulnerability beyond the ability to submit a modified data model file to the server. No network exposure is required if the attacker can influence the model file locally; however, if the server exposes an API to ingest these models, the attack surface extends to any network-authenticated or unauthenticated user capable of reaching that endpoint."
}