CVE-2026-16584

Improper handling of an initialization failure in AWS API MCP Server from 0.2.13 through 1.3.46 might allow an actor to bypass the user-configured security policy and execute AWS API operations that the policy was set to deny or gate. When initialization of the security policy enforcement data fails at server startup, the policy check is skipped for the lifetime of the process. IAM permissions on the configured credentials remain in effect and are unaffected. To remediate this issue, users should upgrade to version 1.3.47.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-063-aws/
https://github.com/awslabs/mcp/security/advisories/GHSA-29w2-fq35-v728
https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.47/

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-23 16:17

Updated : 2026-07-23 19:16

NVD link : CVE-2026-16584

Mitre link : CVE-2026-16584

CVE.ORG link : CVE-2026-16584

JSON object : View

Products Affected

No product.

CWE

CWE-455

Non-exit on Failed Initialization

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