PYSEC-2026-3551

Summary

The AWS Bedrock AgentCore Python SDK (bedrock-agentcore) provides tools for building AI agents, including a Code Interpreter client that installs Python packages into a managed sandbox. An issue exists where, under certain circumstances, improper neutralization of argument delimiters in the install_packages() method allows a remote authenticated user to execute arbitrary commands within the Code Interpreter sandbox via crafted package name arguments.

Impact

Insufficient input validation in installpackages() allows specially crafted package specifiers to bypass validation and achieve arbitrary command execution within the sandbox. A remote authenticated user who can influence the arguments to installpackages() can execute arbitrary commands within the Code Interpreter sandbox environment.

Impacted Versions

< 1.18.1

Patches

This issue has been addressed in bedrock-agentcore version 1.18.1. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.

Workarounds

If you are not able to upgrade, do not pass untrusted or model-generated input to install_packages(). Applications that must accept dynamic package names should validate them against strict PyPI naming rules -- including constraining any extras group to comma-separated identifiers -- before calling the SDK.

References

If you have any questions or comments about this advisory, AWS asks that you contact AWS Security via the vulnerability reporting page or directly via email to aws-security@amazon.com. Please do not create a public GitHub issue.

Acknowledgement

AWS would like to thank Sergio Garcia (@MrCloudSec) for collaborating on this issue through the coordinated issue disclosure process.