{"cve":"CVE-2026-16584","nvd":{"published":"2026-07-23T16:17:15.787","modified":"2026-10-24T13:10:00.147","status":"Awaiting Analysis","description":"Improper handling of an initialization failure in AWS API MCP Server from 0.2.13 through 1.3.46 might allow an actor to bypass the user-configured security policy and execute AWS API operations that the policy was set to deny or gate. When initialization of the security policy enforcement data fails at server startup, the policy check is skipped for the lifetime of the process. IAM permissions on the configured credentials remain in effect and are unaffected.\n\n\n\nTo remediate this issue, users should upgrade to version 1.3.47.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":7.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","score":7.0},"cwes":["CWE-455"],"references":["https://aws.amazon.com/security/security-bulletins/2026-063-aws/","https://github.com/awslabs/mcp/security/advisories/GHSA-29w2-fq35-v728","https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.47/"],"products":[],"source":"nvd","synced_at":"2026-10-24T16:53:27.712498749+00:00"},"epss":{"cve":"CVE-2026-16584","score":0.00227,"percentile":0.13281,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-29w2-fq35-v728","url":"https://osv.dev/vulnerability/GHSA-29w2-fq35-v728","summary":"AWS API MCP Server Security Policy Bypass via Startup Initialization Failure","modified":"2026-08-04T14:41:05.889987689Z","packages":[{"ecosystem":"PyPI","name":"awslabs-aws-api-mcp-server","purl":"pkg:pypi/awslabs-aws-api-mcp-server","ranges":[">=0.2.13 <1.3.47"],"fixed":["1.3.47"]}]},{"id":"PYSEC-2026-3549","url":"https://osv.dev/vulnerability/PYSEC-2026-3549","summary":"AWS API MCP Server Security Policy Bypass via Startup Initialization Failure","modified":"2026-08-04T14:30:24.402881095Z","packages":[{"ecosystem":"PyPI","name":"awslabs-aws-api-mcp-server","purl":"pkg:pypi/awslabs-aws-api-mcp-server","ranges":[">=0.2.13 <1.3.47"],"fixed":["1.3.47"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}