Riskcovery

CVE-2026-4269

Improper S3 ownership verification in Bedrock AgentCore Starter Toolkit

State
Published
Severity
5.8 Medium
Published
Mar 16, 2026
Updated
Mar 16, 2026
Reserved
Mar 16, 2026

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
4.05.8 MediumCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:HAMZN
3.17.5 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:HAMZN

Weaknesses

  • CWE-340 Generation of Predictable Numbers or Identifiers
  • CWE-283 Unverified Ownership

Affected Products

ProductVersions
Bedrock AgentCore Starter ToolkitAWS
  • 0.1.0 to before 0.1.13Affected

References

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