CVE-2026-4269 (GCVE-0-2026-4269)
Vulnerability from cvelistv5 – Published: 2026-03-16 18:03 – Updated: 2026-03-16 18:12
VLAI
EPSS
VEX
Title
Improper S3 ownership verification in Bedrock AgentCore Starter Toolkit
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-16 18:11 UTC
Assigner
AMZN
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/aws/bedrock-agentcore-starter-… | patch |
| https://aws.amazon.com/security/security-bulletin… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| AWS | Bedrock AgentCore Starter Toolkit |
Affected:
0.1.0 , < 0.1.13
(custom)
|
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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