CVE-2026-15957

{
  "id": "CVE-2026-15957",
  "sourceIdentifier": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
  "published": "2026-07-21T20:16:58.780",
  "lastModified": "2026-10-24T19:10:00.127",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Smithy-RS is a Rust code generation and runtime framework that generates HTTP clients and servers from Smithy interface definitions, powering the AWS SDK for Rust and custom service implementations.\n\n\n\nUncontrolled recursion in the JSON, CBOR, and XML deserializer functions emitted by Amazon smithy-rs code generation could allow remote attackers to cause a denial of service (process abort via stack exhaustion) via a small request containing deeply nested data for a recursive model shape to a generated SDK or server.\n\n\n\nTo mitigate this issue, users should upgrade to aws-sdk-rust release-2026-06-02 or later. Users building custom servers with smithy-rs codegen should regenerate from smithy-rs release-2026-06-01 or later."
    },
    {
      "lang": "es",
      "value": "Smithy-RS es un framework de generación de código y tiempo de ejecución de Rust que genera clientes y servidores HTTP a partir de definiciones de interfaz de Smithy, impulsando el SDK de AWS para Rust e implementaciones de servicios personalizados.\n\nLa recursión incontrolada en las funciones deserializadoras de JSON, CBOR y XML emitidas por la generación de código de Amazon smithy-rs podría permitir a atacantes remotos causar una denegación de servicio (aborto de proceso por agotamiento de la pila) a través de una pequeña solicitud que contenga datos profundamente anidados para una forma de modelo recursivo a un SDK o servidor generado.\n\nPara mitigar este problema, los usuarios deberían actualizar a aws-sdk-rust release-2026-06-02 o posterior. Los usuarios que construyen servidores personalizados con smithy-rs codegen deberían regenerar a partir de smithy-rs release-2026-06-01 o posterior."
    }
  ],
  "affected": [
    {
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
      "affectedData": [
        {
          "vendor": "AWS",
          "product": "aws-sdk-rust",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "lessThan": "release-2026-06-02",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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": 8.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-22T18:15:34.870880Z",
          "id": "CVE-2026-15957",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-674"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://aws.amazon.com/security/security-bulletins/2026-061-aws/",
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
    },
    {
      "url": "https://github.com/awslabs/aws-sdk-rust/releases/tag/release-2026-06-02",
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
    },
    {
      "url": "https://github.com/smithy-lang/smithy-rs/security/advisories/GHSA-4f2p-7j38-4xrg",
      "source": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
    }
  ]
}