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CVE-2026-16584

Full vulnerability record from the local CVENow database.

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. To remediate this issue, users should upgrade to version 1.3.47.

Severity
HIGH
CVSS score
7.3 (v4.0)
Vulnerability status
Awaiting Analysis
Source identifier
ff89ba41-3aa1-4d27-914a-91399e9639e5
Published
2026-07-23 16:17:15.787000
Last modified
2026-10-24 13:10:00.147000
View original CVE JSON
{
  "id": "CVE-2026-16584",
  "sourceIdentifier": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
  "published": "2026-07-23T16:17:15.787",
  "lastModified": "2026-10-24T13:10:00.147",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "El manejo inadecuado de un fallo de inicialización en el servidor AWS API MCP desde la versión 0.2.13 hasta la 1.3.46 podría permitir a un actor eludir la política de seguridad configurada por el usuario y ejecutar operaciones de la API de AWS que la política estaba configurada para denegar o restringir. Cuando falla la inicialización de los datos de aplicación de la política de seguridad al inicio del servidor, la verificación de la política se omite durante la vida útil del proceso. Los permisos de IAM sobre las credenciales configuradas permanecen en vigor y no se ven afectados.\n\nPara solucionar este problema, los usuarios deben actualizar a la versión 1.3.47."
    }
  ],
  "affected": [
    {
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
      "affectedData": [
        {
          "vendor": "AWS",
          "product": "aws-api-mcp-server",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0.2.13",
              "lessThan": "1.3.47",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 7.3,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "privilegesRequired": "NONE",
          "userInteraction": "PASSIVE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "baseScore": 7.0,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-23T18:16:30.277311Z",
          "id": "CVE-2026-16584",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-455"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://aws.amazon.com/security/security-bulletins/2026-063-aws/",
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
    },
    {
      "url": "https://github.com/awslabs/mcp/security/advisories/GHSA-29w2-fq35-v728",
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
    },
    {
      "url": "https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.47/",
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
    }
  ]
}