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CVE-2026-47220

Full vulnerability record from the local CVENow database.

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.37.0 until 1.37.5 and 1.38.3, when the %REQUESTED_SERVER_NAME(X:Y)% is used in log format and host related options is specified, like HOST_FIRST, SNI_FIRST, it's possible to crash Envoy when the specified host header is missing in the request headers. This vulnerability is fixed in 1.37.5 and 1.38.3.

Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-06-26 19:16:41.173000
Last modified
2026-10-25 17:10:00.197000
View original CVE JSON
{
  "id": "CVE-2026-47220",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-26T19:16:41.173",
  "lastModified": "2026-10-25T17:10:00.197",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.37.0 until 1.37.5 and 1.38.3, when the %REQUESTED_SERVER_NAME(X:Y)% is used in log format and host related options is specified, like HOST_FIRST, SNI_FIRST, it's possible to crash Envoy when the specified host header is missing in the request headers. This vulnerability is fixed in 1.37.5 and 1.38.3."
    },
    {
      "lang": "es",
      "value": "Envoy es un proxy de borde y de servicio de código abierto diseñado para aplicaciones nativas de la nube. Desde la versión 1.37.0 hasta la 1.37.5 y la 1.38.3, cuando se utiliza el %REQUESTED_SERVER_NAME(X:Y)% en el formato de registro y se especifican opciones relacionadas con el host, como HOST_FIRST, SNI_FIRST, es posible bloquear Envoy si falta el encabezado de host especificado en los encabezados de la solicitud. Esta vulnerabilidad está corregida en las versiones 1.37.5 y 1.38.3."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "envoyproxy",
          "product": "envoy",
          "versions": [
            {
              "version": ">= 1.38.0, < 1.38.3",
              "status": "affected"
            },
            {
              "version": ">= 1.37.0, < 1.37.5",
              "status": "affected"
            }
          ]
        }
      ]
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "OpenShift Service Mesh 2",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift-service-mesh/proxyv2-rhel9",
          "cpes": [
            "cpe:/a:redhat:service_mesh:2"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "OpenShift Service Mesh 3",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "openshift-service-mesh/istio-proxyv2-rhel9",
          "cpes": [
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  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "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
      },
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        "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
        "type": "Secondary",
        "cvssData": {
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          "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": "2026-06-29T13:26:27.302143Z",
          "id": "CVE-2026-47220",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ]
    },
    {
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
      "type": "Secondary",
      "description": [
        {
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          "value": "CWE-476"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "1.37.0",
              "versionEndExcluding": "1.37.5",
              "matchCriteriaId": "2057BF79-00D1-4154-9DC0-3F278C72F4E1"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "1.38.0",
              "versionEndExcluding": "1.38.3",
              "matchCriteriaId": "2A218AD4-BF4B-46EA-96D7-3B25B7E71AC8"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-47220",
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2493652",
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
    },
    {
      "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
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    {
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47220.json",
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
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  ]
}