Search threats, CVEs… ⌘K
Back to vendor advisories
AWS Security BulletinsCVE-2026-4269

CVE-2026-4269 - Improper S3 ownership verification in Bedrock AgentCore Starter Toolkit

Bulletin ID: 2026-008-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 2026/03/16 11:15 AM PDT 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. Impacted versions: All versions of Bedrock AgentCore Starter Toolkit versions before v0.1.13. This issue only affects users of the Bedrock AgentCore Starter Toolkit before version v0.1.13 who build 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. Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.

Read the vendor bulletin
Not listedCVSS not listedNot listed severity
Scope

What the vendor says is affected

The collected bulletin did not provide a separate affected-products list. Check the original bulletin before making an exposure decision.

Update history

What changed in later vendor updates

SecurityAlert records field-level changes from the point we begin following a bulletin. Earlier vendor changes may not have a field-by-field record.

    • The vendor changed the advisory's last-updated date.
Timeline

When this advisory changed

  1. Added to SecurityAlert

    We collected the advisory from the official source.

  2. Published by AWS

    The publication date reported by the vendor.

  3. Confirmed at the source

    Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory

CVE-2026-4269View CVSS, KEV, EPSS, and threat context
Keep investigating
See every advisory from this vendor