Missing Token Audience Validation in AWS API MCP Server
CVE-2026-115413

7.3HIGH

Key Information:

Vendor

Aws

Status
Aws-api-mcp-server
Vendor
CVE Published:
27 October 2026

What is CVE-2026-115413?

The AWS API MCP Server prior to version 1.6.0 contains a flaw in its OAuth authentication mode due to insufficient token audience validation. This vulnerability allows local users to exploit the server by executing AWS operations with the server's configured AWS credentials using an access token that is issued to another application by the same identity provider. To prevent unauthorized access, it’s essential for users to upgrade to version 1.6.0 and properly configure the expected token audience or client ID to secure their API operations.

Affected Version(s)

aws-api-mcp-server 1.3.0 < 1.6.0

References

https://pypi.org/project/awslabs.aws-api-mcp-server/1.6.0/
release-notespatch
https://github.com/awslabs/mcp/security/advisories/GHSA-4...
third-party-advisory
https://aws.amazon.com/security/security-bulletins/2026-1...
vendor-advisory

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:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.