GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2022-21656 (GCVE-0-2022-21656)

Vulnerability from cvelistv5 – Published: 2022-02-22 22:25 – Updated: 2025-04-23 19:01
VLAI
Title
X.509 subjectAltName matching bypass in Envoy
Summary
Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a "type confusion" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted.
Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-04-23 15:55 UTC
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Vendor Product Version CPE status
envoyproxy envoy Affected: < 1.20.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T02:46:39.567Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2022-21656",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-04-23T15:55:47.477332Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-04-23T19:01:38.563Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "envoy",
          "vendor": "envoyproxy",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.20.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a \"type confusion\" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-295",
              "description": "CWE-295: Improper Certificate Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2022-02-22T22:25:11.000Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e"
        }
      ],
      "source": {
        "advisory": "GHSA-c9g7-xwcv-pjx2",
        "discovery": "UNKNOWN"
      },
      "title": "X.509 subjectAltName matching bypass in Envoy",
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security-advisories@github.com",
          "ID": "CVE-2022-21656",
          "STATE": "PUBLIC",
          "TITLE": "X.509 subjectAltName matching bypass in Envoy"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "envoy",
                      "version": {
                        "version_data": [
                          {
                            "version_value": "\u003c 1.20.2"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "envoyproxy"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "value": "Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a \"type confusion\" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted."
            }
          ]
        },
        "impact": {
          "cvss": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          }
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "CWE-295: Improper Certificate Validation"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2",
              "refsource": "CONFIRM",
              "url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2"
            },
            {
              "name": "https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e",
              "refsource": "MISC",
              "url": "https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e"
            }
          ]
        },
        "source": {
          "advisory": "GHSA-c9g7-xwcv-pjx2",
          "discovery": "UNKNOWN"
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2022-21656",
    "datePublished": "2022-02-22T22:25:11.000Z",
    "dateReserved": "2021-11-16T00:00:00.000Z",
    "dateUpdated": "2025-04-23T19:01:38.563Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2022-21656",
      "date": "2026-09-17",
      "epss": "0.00672",
      "percentile": "0.50424"
    },
    "fkie_nvd": {
      "configurations": "[{\"nodes\": [{\"operator\": \"OR\", \"negate\": false, \"cpeMatch\": [{\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*\", \"versionEndExcluding\": \"1.20.2\", \"matchCriteriaId\": \"E93E9C64-FAEC-494D-82CA-2AD4381EFE52\"}]}]}]",
      "descriptions": "[{\"lang\": \"en\", \"value\": \"Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a \\\"type confusion\\\" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted.\"}, {\"lang\": \"es\", \"value\": \"Envoy es un proxy de borde y servicio de c\\u00f3digo abierto, dise\\u00f1ado para aplicaciones nativas de la nube. La implementaci\\u00f3n default_validator.cc usada para implementar las rutinas de comprobaci\\u00f3n de certificados por defecto presenta un error de \\\"confusi\\u00f3n de tipo\\\" cuando procesa subjectAltNames. Este procesamiento permite, por ejemplo, que un rfc822Name o uniformResourceIndicator sea autenticado como un nombre de dominio. Esta confusi\\u00f3n permite omitir nameConstraints, tal y como lo procesa la implementaci\\u00f3n subyacente de OpenSSL/BoringSSL, exponiendo la posibilidad de suplantaci\\u00f3n de servidores arbitrarios. Como resultado, Envoy confiar\\u00e1 en certificados de origen que no deber\\u00edan ser confiables\"}]",
      "id": "CVE-2022-21656",
      "lastModified": "2024-11-21T06:45:10.103",
      "metrics": "{\"cvssMetricV31\": [{\"source\": \"security-advisories@github.com\", \"type\": \"Secondary\", \"cvssData\": {\"version\": \"3.1\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N\", \"baseScore\": 7.4, \"baseSeverity\": \"HIGH\", \"attackVector\": \"NETWORK\", \"attackComplexity\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"NONE\", \"scope\": \"UNCHANGED\", \"confidentialityImpact\": \"HIGH\", \"integrityImpact\": \"HIGH\", \"availabilityImpact\": \"NONE\"}, \"exploitabilityScore\": 2.2, \"impactScore\": 5.2}, {\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"3.1\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N\", \"baseScore\": 5.9, \"baseSeverity\": \"MEDIUM\", \"attackVector\": \"NETWORK\", \"attackComplexity\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"NONE\", \"scope\": \"UNCHANGED\", \"confidentialityImpact\": \"NONE\", \"integrityImpact\": \"HIGH\", \"availabilityImpact\": \"NONE\"}, \"exploitabilityScore\": 2.2, \"impactScore\": 3.6}], \"cvssMetricV2\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"2.0\", \"vectorString\": \"AV:N/AC:M/Au:N/C:P/I:P/A:N\", \"baseScore\": 5.8, \"accessVector\": \"NETWORK\", \"accessComplexity\": \"MEDIUM\", \"authentication\": \"NONE\", \"confidentialityImpact\": \"PARTIAL\", \"integrityImpact\": \"PARTIAL\", \"availabilityImpact\": \"NONE\"}, \"baseSeverity\": \"MEDIUM\", \"exploitabilityScore\": 8.6, \"impactScore\": 4.9, \"acInsufInfo\": false, \"obtainAllPrivilege\": false, \"obtainUserPrivilege\": false, \"obtainOtherPrivilege\": false, \"userInteractionRequired\": false}]}",
      "published": "2022-02-22T23:15:11.223",
      "references": "[{\"url\": \"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\", \"source\": \"security-advisories@github.com\", \"tags\": [\"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\", \"source\": \"security-advisories@github.com\", \"tags\": [\"Issue Tracking\", \"Third Party Advisory\"]}, {\"url\": \"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Patch\", \"Third Party Advisory\"]}, {\"url\": \"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Issue Tracking\", \"Third Party Advisory\"]}]",
      "sourceIdentifier": "security-advisories@github.com",
      "vulnStatus": "Modified",
      "weaknesses": "[{\"source\": \"security-advisories@github.com\", \"type\": \"Secondary\", \"description\": [{\"lang\": \"en\", \"value\": \"CWE-295\"}]}, {\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"description\": [{\"lang\": \"en\", \"value\": \"CWE-843\"}]}]"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2022-21656\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2022-02-22T23:15:11.223\",\"lastModified\":\"2026-06-17T04:26:41.863\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a \\\"type confusion\\\" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted.\"},{\"lang\":\"es\",\"value\":\"Envoy es un proxy de borde y servicio de c\u00f3digo abierto, dise\u00f1ado para aplicaciones nativas de la nube. La implementaci\u00f3n default_validator.cc usada para implementar las rutinas de comprobaci\u00f3n de certificados por defecto presenta un error de \\\"confusi\u00f3n de tipo\\\" cuando procesa subjectAltNames. Este procesamiento permite, por ejemplo, que un rfc822Name o uniformResourceIndicator sea autenticado como un nombre de dominio. Esta confusi\u00f3n permite omitir nameConstraints, tal y como lo procesa la implementaci\u00f3n subyacente de OpenSSL/BoringSSL, exponiendo la posibilidad de suplantaci\u00f3n de servidores arbitrarios. Como resultado, Envoy confiar\u00e1 en certificados de origen que no deber\u00edan ser confiables\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"envoyproxy\",\"product\":\"envoy\",\"versions\":[{\"version\":\"\u003c 1.20.2\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N\",\"baseScore\":7.4,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.2,\"impactScore\":5.2},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N\",\"baseScore\":5.9,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.2,\"impactScore\":3.6}],\"cvssMetricV2\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"2.0\",\"vectorString\":\"AV:N/AC:M/Au:N/C:P/I:P/A:N\",\"baseScore\":5.8,\"accessVector\":\"NETWORK\",\"accessComplexity\":\"MEDIUM\",\"authentication\":\"NONE\",\"confidentialityImpact\":\"PARTIAL\",\"integrityImpact\":\"PARTIAL\",\"availabilityImpact\":\"NONE\"},\"baseSeverity\":\"MEDIUM\",\"exploitabilityScore\":8.6,\"impactScore\":4.9,\"acInsufInfo\":false,\"obtainAllPrivilege\":false,\"obtainUserPrivilege\":false,\"obtainOtherPrivilege\":false,\"userInteractionRequired\":false}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2025-04-23T15:55:47.477332Z\",\"id\":\"CVE-2022-21656\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"total\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-295\"}]},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-843\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"1.20.2\",\"matchCriteriaId\":\"E93E9C64-FAEC-494D-82CA-2AD4381EFE52\"}]}]}],\"references\":[{\"url\":\"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Issue Tracking\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Patch\",\"Third Party Advisory\"]},{\"url\":\"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Issue Tracking\",\"Third Party Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2025-11-21T15:15:25+00:00",
      "cve": "CVE-2022-21656",
      "id": "CVE-2022-21656",
      "initial_release_date": "2022-02-23T00:00:00+00:00",
      "product_status:known_affected": "5",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "envoy: X.509 subjectAltName matching (and nameConstraints) bypass",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2022/cve-2022-21656.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2025-02-16T07:45:07Z",
      "cve": "CVE-2022-21656",
      "id": "CVE-2022-21656",
      "initial_release_date": "2023-02-15T03:29:11Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2022-21656",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2022-21656.json",
      "version": "5"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\", \"tags\": [\"x_refsource_CONFIRM\", \"x_transferred\"]}, {\"url\": \"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\", \"tags\": [\"x_refsource_MISC\", \"x_transferred\"]}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2024-08-03T02:46:39.567Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2022-21656\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-04-23T15:55:47.477332Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-04-23T15:55:49.068Z\"}}], \"cna\": {\"title\": \"X.509 subjectAltName matching bypass in Envoy\", \"source\": {\"advisory\": \"GHSA-c9g7-xwcv-pjx2\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.4, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"envoyproxy\", \"product\": \"envoy\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 1.20.2\"}]}], \"references\": [{\"url\": \"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a \\\"type confusion\\\" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-295\", \"description\": \"CWE-295: Improper Certificate Validation\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2022-02-22T22:25:11.000Z\"}, \"x_legacyV4Record\": {\"impact\": {\"cvss\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.4, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}}, \"source\": {\"advisory\": \"GHSA-c9g7-xwcv-pjx2\", \"discovery\": \"UNKNOWN\"}, \"affects\": {\"vendor\": {\"vendor_data\": [{\"product\": {\"product_data\": [{\"version\": {\"version_data\": [{\"version_value\": \"\u003c 1.20.2\"}]}, \"product_name\": \"envoy\"}]}, \"vendor_name\": \"envoyproxy\"}]}}, \"data_type\": \"CVE\", \"references\": {\"reference_data\": [{\"url\": \"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\", \"name\": \"https://github.com/envoyproxy/envoy/security/advisories/GHSA-c9g7-xwcv-pjx2\", \"refsource\": \"CONFIRM\"}, {\"url\": \"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\", \"name\": \"https://github.com/envoyproxy/envoy/commit/bb95af848c939cfe5b5ee33c5b1770558077e64e\", \"refsource\": \"MISC\"}]}, \"data_format\": \"MITRE\", \"description\": {\"description_data\": [{\"lang\": \"eng\", \"value\": \"Envoy is an open source edge and service proxy, designed for cloud-native applications. The default_validator.cc implementation used to implement the default certificate validation routines has a \\\"type confusion\\\" bug when processing subjectAltNames. This processing allows, for example, an rfc822Name or uniformResourceIndicator to be authenticated as a domain name. This confusion allows for the bypassing of nameConstraints, as processed by the underlying OpenSSL/BoringSSL implementation, exposing the possibility of impersonation of arbitrary servers. As a result Envoy will trust upstream certificates that should not be trusted.\"}]}, \"problemtype\": {\"problemtype_data\": [{\"description\": [{\"lang\": \"eng\", \"value\": \"CWE-295: Improper Certificate Validation\"}]}]}, \"data_version\": \"4.0\", \"CVE_data_meta\": {\"ID\": \"CVE-2022-21656\", \"STATE\": \"PUBLIC\", \"TITLE\": \"X.509 subjectAltName matching bypass in Envoy\", \"ASSIGNER\": \"security-advisories@github.com\"}}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2022-21656\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2025-04-23T19:01:38.563Z\", \"dateReserved\": \"2021-11-16T00:00:00.000Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2022-02-22T22:25:11.000Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.