CVE-2026-4269

High

Description

A missing S3 ownership verification in the Bedrock AgentCore Starter Toolkit before version v0.1.13 may allow a remote actor to inject code during the build process, leading to code execution in the AgentCore Runtime. This issue only affects users of the Bedrock AgentCore Starter Toolkit before version v0.1.13 who build or have built the Toolkit after September 24, 2025. Any users on a version >=v0.1.13, and any users on previous versions who built the toolkit before September 24, 2025 are not affected. To remediate this issue, customers should upgrade to version v0.1.13.

SeverityHigh
CVSS7.5
Exploit probability—
ProductAmazon Bedrock Agentcore Starter Toolkit
PublishedMar 16, 2026
First seenMar 16, 2026

How to fix

Update
  • amazon bedrock_agentcore_starter_toolkit0.1.13 or later
  • bedrock-agentcore-starter-toolkit0.1.13 or later

Affected products

ProductAffected versionsFixed in
amazon bedrock_agentcore_starter_toolkitv < 0.1.130.1.13
bedrock-agentcore-starter-toolkitPyPIv < 0.1.130.1.13

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