cve.bz

CVE-2026-4269

5.8 mediumEPSS 0.3%

Medium (5.8) in amazon bedrock agentcore starter toolkit. EPSS 0.3% chance of exploitation in the next 30 days. Fixed in bedrock-agentcore-starter-toolkit 0.1.13.

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

CVSS 4.0

5.8 medium
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H

CVSS 3.1

7.5 high
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
0.3% chance of exploitation in the next 30 days; higher than 16% of CVEs (scores of 2026-10-31)
CWEs
CWE-283, CWE-340
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-xfhr-q72q-jcrjPyPIbedrock-agentcore-starter-toolkit<0.1.130.1.13
PYSEC-2026-2396PyPIbedrock-agentcore-starter-toolkit<0.1.130.1.13

References

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