CVE-2026-4270
5.5 · MEDIUMOverview
CVE-2026-4270 is a medium-severity vulnerability affecting amazon aws_api_mcp_server. It was published on March 16, 2026 and has a CVSS 3.1 base score of 5.5 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.5, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from amazon. Update aws_api_mcp_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| amazon | aws_api_mcp_server | >= 0.2.14, < 1.3.9 | Affected |
Frequently Asked Questions
What is CVE-2026-4270?
CVE-2026-4270 is a medium-severity vulnerability affecting amazon aws_api_mcp_server. It was published on March 16, 2026 and has a CVSS 3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2026-4270?
This vulnerability has a CVSS 3.1 base score of 5.5, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-4270?
Check the references section for vendor advisories and patches from amazon. Update aws_api_mcp_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-4270?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-4270 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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