CVE-2026-11393 - Code Injection via Improper Triple-Quote Escaping in AgentCore CLI Bedrock Agent Import

Bulletin ID: 2026-040-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 06/08/2026 11:45 AM PDT Description: The AWS AgentCore CLI (@aws/agentcore) is a developer tool for managing agent infrastructure lifecycle on Amazon Bedrock AgentCore. We identified CVE-2026-11393 in which improper neutralization of triple-quote characters during Python code generation may allow an authenticated user in the same AWS account to inject arbitrary Python code into the source file generated by the "agentcore add agent ‐‐type import" command. Specifically, the collaborationInstruction field of a Bedrock Agent collaborator association was interpolated into a triple-quoted Python docstring using single-quote escaping rather than triple-quote escaping. A user with bedrock:AssociateAgentCollaborator IAM permission could craft a collaborationInstruction value containing """ to break out of the docstring boundary in the generated main.py of the imported agent. If that generated file was subsequently executed - either via agentcore dev on the developer's local machine, or via agentcore deploy followed by agentcore invoke in the AgentCore Runtime environment - the injected Python would run with the credentials available in that context. Impacted versions: - @aws/agentcore >= 0.4.0 AND <= 0.14.1 - preview versions >= 0.3.0-preview.7.0 and <= 1.0.0-preview.8 Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.