CVE•Published 2026-03-16•Modified 2026-05-21•0 articles on news•6 live references•NVD data

CVE-2026-4270Amazon · Aws_api_mcp_server

Vulnerability data via NVD (ingested)

CVSS v3.1

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS percentile

Exploit Prediction Scoring System · top 97% of all CVEs

Weaknesses (CWE)

CWE-424Improper Protection of Alternate Path

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.

Timeline

Published 2026-03-16

Modified 2026-05-21

External references

NVD MITRE Exploit-DB GitHub PoC Sploitus VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-4270

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Amazon Aws Api Mcp Server"

All exposed Amazon Aws Api Mcp Server instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Aws Api Mcp Server"

HTTP body or banner mentions "Aws Api Mcp Server" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-4270