FKIE_CVE-2026-40701

Vulnerability from fkie_nvd - Published: 2026-05-13 16:16 - Updated: 2026-10-26 17:10
Severity
4.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Summary
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.
References
f5sirt@f5.comhttps://my.f5.com/manage/s/article/K000161021Mitigation, Vendor Advisory
Impacted products
Vendor Product Version
f5 dos *
f5 dos 4.8.0
f5 nginx_gateway_fabric *
f5 nginx_gateway_fabric *
f5 nginx_ingress_controller *
f5 nginx_ingress_controller *
f5 nginx_ingress_controller *
f5 nginx_instance_manager *
f5 nginx_open_source *
f5 nginx_plus *
f5 waf *
f5 waf *
f5 waf *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unknown",
          "modules": [
            "ngx_http_ssl_module"
          ],
          "product": "NGINX Plus",
          "vendor": "F5",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "R37",
              "versionType": "custom"
            },
            {
              "lessThan": "R36 P4",
              "status": "affected",
              "version": "R36",
              "versionType": "custom"
            },
            {
              "lessThan": "R32 P6",
              "status": "affected",
              "version": "R32",
              "versionType": "custom"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "modules": [
            "ngx_http_ssl_module"
          ],
          "product": "NGINX Open Source",
          "vendor": "F5",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "1.31.0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.30.1",
              "status": "affected",
              "version": "1.19.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "f5sirt@f5.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
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              "vulnerable": true
            },
            {
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              "matchCriteriaId": "C45452BD-7A86-48E7-8E1D-1B340FF70B3B",
              "vulnerable": true
            },
            {
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              "versionEndIncluding": "5.4.2",
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            },
            {
              "criteria": "cpe:2.3:a:f5:nginx_instance_manager:*:*:*:*:*:*:*:*",
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              "versionEndIncluding": "2.22.0",
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            {
              "criteria": "cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*",
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              "versionEndIncluding": "1.30.0",
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            {
              "criteria": "cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "0B153576-468F-48C2-9BC8-922A938AB235",
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            {
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            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssl_module\u00a0module when the ssl_verify_client\u00a0directive is set to \"on\" or \"optional,\" and the ssl_ocsp\u00a0directive is set to \"on\" or the leaf\u00a0parameters 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\u00a0Note: 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 m\u00f3dulo ngx_http_ssl_module cuando la directiva ssl_verify_client est\u00e1 configurada como \u2019on\u2019 u \u2019optional\u2019, y la directiva ssl_ocsp est\u00e1 configurada como \u2019on\u2019 o los par\u00e1metros leaf est\u00e1n configurados con un resolvedor. Con esta configuraci\u00f3n, 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 modificaci\u00f3n 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 T\u00e9cnico (EoTS) no se eval\u00faan."
    }
  ],
  "id": "CVE-2026-40701",
  "lastModified": "2026-10-26T17:10:03.270",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 2.5,
        "source": "f5sirt@f5.com",
        "type": "Secondary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 6.3,
          "baseSeverity": "MEDIUM",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "LOW",
          "vulnConfidentialityImpact": "LOW",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "f5sirt@f5.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-40701",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-13T15:55:34.604451Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-13T16:16:43.863",
  "references": [
    {
      "source": "f5sirt@f5.com",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ],
      "url": "https://my.f5.com/manage/s/article/K000161021"
    }
  ],
  "sourceIdentifier": "f5sirt@f5.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "f5sirt@f5.com",
      "type": "Secondary"
    }
  ]
}



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