Initialization Failure in AWS API MCP Server Allows Bypassing Security Policies
CVE-2026-16584

7.3HIGH

Key Information:

Vendor

Aws

Status
Aws-api-mcp-server
Vendor
CVE Published:
23 July 2026

What is CVE-2026-16584?

An improper handling of initialization failures in AWS API MCP Server versions 0.2.13 to 1.3.46 allows potential attackers to bypass user-configured security policies and perform AWS API operations that would normally be denied. This issue occurs when the enforcement of security policy initialization fails during server startup, leading to skipped policy checks for the life of the process. While IAM permissions remain intact, the vulnerability poses significant risks as it can enable unauthorized API access. Users are advised to upgrade to version 1.3.47 to mitigate this vulnerability.

Affected Version(s)

aws-api-mcp-server 0.2.13 < 1.3.47

References

https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.47/
release-notespatch
https://aws.amazon.com/security/security-bulletins/2026-0...
vendor-advisory
https://github.com/awslabs/mcp/security/advisories/GHSA-2...
release-notes

CVSS V4

Score:
7.3
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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