CVE-2026-4270

Improper Protection of Alternate Path exists in the no-access and workdir feature of the AWS API MCP Server versions >= 0.2.14 and < 1.3.9 on all platforms may allow the bypass of intended file access restriction and expose arbitrary local file contents in the MCP client application context. To remediate this issue, users should upgrade to version 1.3.9.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-007-AWS/	Vendor Advisory
https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.9/	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:amazon:aws_api_mcp_server:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-03-16 17:16

Updated : 2026-06-17 10:56

NVD link : CVE-2026-4270

Mitre link : CVE-2026-4270

CVE.ORG link : CVE-2026-4270

JSON object : View

Products Affected

amazon

aws_api_mcp_server

CWE

CWE-424

Improper Protection of Alternate Path

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