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CVE-2026-40701

Full vulnerability record from the local CVENow database.

Description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssl_module module when the ssl_verify_client directive is set to "on" or "optional," and the ssl_ocsp directive is set to "on" or the leaf parameters are configured with a resolver. With this configuration, an unauthenticated attacker can send requests along with conditions beyond its control that may cause a heap-use-after-free error in the NGINX worker process. This vulnerability may result in limited modification of data or the NGINX worker process restarting.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Severity
MEDIUM
CVSS score
6.3 (v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-05-13 16:16:43.863000
Last modified
2026-10-26 17:10:03.270000
View original CVE JSON
{
  "id": "CVE-2026-40701",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-13T16:16:43.863",
  "lastModified": "2026-10-26T17:10:03.270",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssl_module module when the ssl_verify_client directive is set to \"on\" or \"optional,\" and the ssl_ocsp directive is set to \"on\" or the leaf parameters are configured with a resolver. With this configuration, an unauthenticated attacker can send requests along with conditions beyond its control that may cause a heap-use-after-free error in the NGINX worker process. This vulnerability may result in limited modification of data or the NGINX worker process restarting.\n\n\n\n Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."
    },
    {
      "lang": "es",
      "value": "NGINX Plus y NGINX Open Source tienen una vulnerabilidad en el módulo ngx_http_ssl_module cuando la directiva ssl_verify_client está configurada como ’on’ u ’optional’, y la directiva ssl_ocsp está configurada como ’on’ o los parámetros leaf están configurados con un resolvedor. Con esta configuración, un atacante no autenticado puede enviar solicitudes junto con condiciones fuera de su control que pueden causar un error de heap-use-after-free en el proceso de trabajador de NGINX. Esta vulnerabilidad puede resultar en una modificación limitada de datos o el reinicio del proceso de trabajador de NGINX.\n\nNota: Las versiones de software que han alcanzado el Fin de Soporte Técnico (EoTS) no se evalúan."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "F5",
          "product": "NGINX Plus",
          "defaultStatus": "unknown",
          "modules": [
            "ngx_http_ssl_module"
          ],
          "versions": [
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              "lessThan": "*",
              "versionType": "custom",
              "status": "unaffected"
            },
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              "versionType": "custom",
              "status": "affected"
            },
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            }
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        },
        {
          "vendor": "F5",
          "product": "NGINX Open Source",
          "defaultStatus": "unaffected",
          "modules": [
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          ],
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            },
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            }
          ]
        }
      ]
    }
  ],
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        "type": "Secondary",
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          "baseScore": 6.3,
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          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "privilegesRequired": "NONE",
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          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "LOW",
          "subConfidentialityImpact": "NONE",
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          "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": "[email protected]",
        "type": "Secondary",
        "cvssData": {
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          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW"
        },
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        "impactScore": 2.5
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-13T15:55:34.604451Z",
          "id": "CVE-2026-40701",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
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          "negate": false,
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  "references": [
    {
      "url": "https://my.f5.com/manage/s/article/K000161021",
      "source": "[email protected]",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ]
    }
  ]
}