← Back to CVE Explorer

CVE-2026-47074

Full vulnerability record from the local CVENow database.

Description

Improper Certificate Validation vulnerability in ex-aws ex_aws_sns (ExAws.SNS, ExAws.SNS.PublicKeyCache modules) allows Signature Spoofing by Improper Validation. This vulnerability is associated with program files lib/ex_aws/sns.ex, lib/ex_aws/sns/public_key_cache.ex and program routines 'Elixir.ExAws.SNS':verify_message/1, 'Elixir.ExAws.SNS.PublicKeyCache':get/1. 'Elixir.ExAws.SNS':verify_message/1 fetches the signing certificate from the SigningCertURL field of the incoming SNS message without validating that the URL uses HTTPS or that the host matches an AWS-owned SNS certificate domain. An unauthenticated attacker who can POST to an endpoint that calls verify_message/1 can supply an attacker-controlled SigningCertURL, sign a forged SNS message with their own key, and cause the function to return :ok, completely bypassing SNS signature verification. This issue affects ex_aws_sns: from 2.0.1 before 2.3.5.

Severity
HIGH
CVSS score
8.7 (v4.0)
Vulnerability status
Deferred
Source identifier
6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Published
2026-05-28 10:16:39.800000
Last modified
2026-10-26 11:10:00.157000
View original CVE JSON 
{
  "id": "CVE-2026-47074",
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "published": "2026-05-28T10:16:39.800",
  "lastModified": "2026-10-26T11:10:00.157",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Improper Certificate Validation vulnerability in ex-aws ex_aws_sns (ExAws.SNS, ExAws.SNS.PublicKeyCache modules) allows Signature Spoofing by Improper Validation.\n\nThis vulnerability is associated with program files lib/ex_aws/sns.ex, lib/ex_aws/sns/public_key_cache.ex and program routines 'Elixir.ExAws.SNS':verify_message/1, 'Elixir.ExAws.SNS.PublicKeyCache':get/1.\n\n'Elixir.ExAws.SNS':verify_message/1 fetches the signing certificate from the SigningCertURL field of the incoming SNS message without validating that the URL uses HTTPS or that the host matches an AWS-owned SNS certificate domain. An unauthenticated attacker who can POST to an endpoint that calls verify_message/1 can supply an attacker-controlled SigningCertURL, sign a forged SNS message with their own key, and cause the function to return :ok, completely bypassing SNS signature verification.\n\nThis issue affects ex_aws_sns: from 2.0.1 before 2.3.5."
    },
    {
      "lang": "es",
      "value": "La vulnerabilidad de validación de certificado incorrecta en ex-aws ex_aws_sns (módulos ExAws.SNS, ExAws.SNS.PublicKeyCache) permite la suplantación de firma por validación incorrecta.\n\nEsta vulnerabilidad está asociada con los archivos de programa lib/ex_aws/sns.ex, lib/ex_aws/sns/public_key_cache.ex y las rutinas de programa ’Elixir.ExAws.SNS’:verify_message/1, ’Elixir.ExAws.SNS.PublicKeyCache’:get/1.\n\n’Elixir.ExAws.SNS’:verify_message/1 obtiene el certificado de firma del campo SigningCertURL del mensaje SNS entrante sin validar que la URL utilice HTTPS o que el host coincida con un dominio de certificado SNS propiedad de AWS. Un atacante no autenticado que puede realizar una solicitud POST a un endpoint que llama a verify_message/1 puede proporcionar una SigningCertURL controlada por el atacante, firmar un mensaje SNS falsificado con su propia clave y hacer que la función devuelva :ok, omitiendo completamente la verificación de firma de SNS.\n\nEste problema afecta a ex_aws_sns: desde 2.0.1 antes de 2.3.5."
    }
  ],
  "affected": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "affectedData": [
        {
          "vendor": "ex-aws",
          "product": "ex_aws_sns",
          "defaultStatus": "unaffected",
          "collectionURL": "https://hex.pm",
          "packageName": "ex_aws_sns",
          "cpes": [
            "cpe:2.3:a:ex_aws_sns_project:ex_aws_sns:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "'Elixir.ExAws.SNS'",
            "'Elixir.ExAws.SNS.PublicKeyCache'"
          ],
          "programFiles": [
            "lib/ex_aws/sns.ex",
            "lib/ex_aws/sns/public_key_cache.ex"
          ],
          "programRoutines": [
            {
              "name": "'Elixir.ExAws.SNS':verify_message/1"
            },
            {
              "name": "'Elixir.ExAws.SNS.PublicKeyCache':get/1"
            }
          ],
          "repo": "https://github.com/ex-aws/ex_aws_sns",
          "packageURL": "pkg:hex/ex_aws_sns",
          "versions": [
            {
              "version": "2.0.1",
              "lessThan": "2.3.5",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "ex-aws",
          "product": "ex_aws_sns",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com",
          "packageName": "ex-aws/ex_aws_sns",
          "cpes": [
            "cpe:2.3:a:ex_aws_sns_project:ex_aws_sns:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "'Elixir.ExAws.SNS'",
            "'Elixir.ExAws.SNS.PublicKeyCache'"
          ],
          "programFiles": [
            "lib/ex_aws/sns.ex",
            "lib/ex_aws/sns/public_key_cache.ex"
          ],
          "programRoutines": [
            {
              "name": "'Elixir.ExAws.SNS':verify_message/1"
            },
            {
              "name": "'Elixir.ExAws.SNS.PublicKeyCache':get/1"
            }
          ],
          "repo": "https://github.com/ex-aws/ex_aws_sns",
          "packageURL": "pkg:github/ex-aws/ex_aws_sns",
          "versions": [
            {
              "version": "a7ec21880943f4dac1d59bda557db0ffcd2b61fa",
              "lessThan": "1853d280b152d10384a1e21a22cf22152a60be48",
              "versionType": "git",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/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": "HIGH",
          "vulnAvailabilityImpact": "NONE",
          "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"
        }
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-28T10:29:45.193313Z",
          "id": "CVE-2026-47074",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-295"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://cna.erlef.org/cves/CVE-2026-47074.html",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/ex-aws/ex_aws_sns/commit/1853d280b152d10384a1e21a22cf22152a60be48",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/ex-aws/ex_aws_sns/security/advisories/GHSA-8jgf-23q5-x7xx",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-47074",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ]
}