FKIE_CVE-2026-42771

Vulnerability from fkie_nvd - Published: 2026-06-09 17:17 - Updated: 2026-07-23 08:10
Severity
6.2 (Medium) - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Issue summary: When the X509_VERIFY_PARAM_set1_email is called by an application to validate a crafted e-mail address, such as during S/MIME message validation, an out of bounds read can happen. Impact summary: This out of bounds read will not directly exfiltrate the data read to the attacker so the most likely result is a crash and a Denial of Service. An internal helper function called from X509_VERIFY_PARAM_[set|add]_email() used a wrong length when validating the local part of an email address. This could cause the 64 octet limit on the local part of an email address to be not enforced, or cause an out of bound read and potentially a crash. The bug is reachable via S-MIME validation with a crafted From: address supplied in an email message that can potentially cause a crash. No FIPS modules are affected by this issue as the affected code is outside the OpenSSL FIPS module boundary.
References
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/6cd187689f8180c1f8a3acde21f88190c4a20de7Patch
openssl-security@openssl.orghttps://openssl-library.org/news/secadv/20260609.txtVendor Advisory
Impacted products
Vendor Product Version
openssl openssl 4.0.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
            {
              "lessThan": "4.0.1",
              "status": "affected",
              "version": "4.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "openssl-security@openssl.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*",
              "matchCriteriaId": "6E881B9A-1A0A-4BC0-8160-20C00561167D",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Issue summary: When the X509_VERIFY_PARAM_set1_email is called by an\napplication to validate a crafted e-mail address, such as during S/MIME\nmessage validation, an out of bounds read can happen.\n\nImpact summary: This out of bounds read will not directly exfiltrate\nthe data read to the attacker so the most likely result is a crash and\na Denial of Service.\n\nAn internal helper function called from X509_VERIFY_PARAM_[set|add]_email()\nused a wrong length when validating the local part of an email address.\nThis could cause the 64 octet limit on the local part of an email address\nto be not enforced, or cause an out of bound read and potentially a crash.\n\nThe bug is reachable via S-MIME validation with a crafted From: address\nsupplied in an email message that can potentially cause a crash.\n\nNo FIPS modules are affected by this issue as the affected code is outside\nthe OpenSSL FIPS module boundary."
    },
    {
      "lang": "es",
      "value": "Resumen del problema: Cuando una aplicaci\u00f3n llama a X509_VERIFY_PARAM_set1_email para validar una direcci\u00f3n de correo electr\u00f3nico manipulada, como durante la validaci\u00f3n de mensajes S/MIME, puede ocurrir una lectura fuera de l\u00edmites.\n\nResumen del impacto: Esta lectura fuera de l\u00edmites no exfiltrar\u00e1 directamente los datos le\u00eddos al atacante, por lo que el resultado m\u00e1s probable es un fallo y una denegaci\u00f3n de servicio.\n\nUna funci\u00f3n auxiliar interna llamada desde X509_VERIFY_PARAM_[set|add]_email() utiliz\u00f3 una longitud incorrecta al validar la parte local de una direcci\u00f3n de correo electr\u00f3nico. Esto podr\u00eda causar que no se aplicara el l\u00edmite de 64 octetos en la parte local de una direcci\u00f3n de correo electr\u00f3nico, o causar una lectura fuera de l\u00edmites y potencialmente un fallo.\n\nEl error es alcanzable a trav\u00e9s de la validaci\u00f3n S-MIME con una direcci\u00f3n From: manipulada proporcionada en un mensaje de correo electr\u00f3nico que puede causar potencialmente un fallo.\n\nNing\u00fan m\u00f3dulo FIPS se ve afectado por este problema, ya que el c\u00f3digo afectado est\u00e1 fuera del l\u00edmite del m\u00f3dulo FIPS de OpenSSL."
    }
  ],
  "id": "CVE-2026-42771",
  "lastModified": "2026-07-23T08:10:00.137",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 6.2,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-42771",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-09T18:59:41.123767Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-09T17:17:08.663",
  "references": [
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/openssl/openssl/commit/6cd187689f8180c1f8a3acde21f88190c4a20de7"
    },
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://openssl-library.org/news/secadv/20260609.txt"
    }
  ],
  "sourceIdentifier": "openssl-security@openssl.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "openssl-security@openssl.org",
      "type": "Secondary"
    }
  ]
}



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