{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.0",
  "cveMetadata": {
    "cveId": "CVE-2026-27137"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc"
      },
      "title": "Incorrect enforcement of email constraints in crypto/x509",
      "descriptions": [
        {
          "lang": "en",
          "value": "When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly applied, and only the last constraint will be considered."
        }
      ],
      "affected": [
        {
          "vendor": "Go standard library",
          "product": "crypto/x509",
          "collectionURL": "https://pkg.go.dev",
          "packageName": "crypto/x509",
          "versions": [
            {
              "version": "1.26.0-0",
              "lessThan": "1.26.1",
              "status": "affected",
              "versionType": "semver"
            }
          ],
          "programRoutines": [
            {
              "name": "newEmailConstraints"
            },
            {
              "name": "emailConstraints.query"
            },
            {
              "name": "checkConstraints"
            },
            {
              "name": "checkChainConstraints"
            },
            {
              "name": "parseMailboxes"
            },
            {
              "name": "Certificate.Verify"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-295: Improper Certificate Validation"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://go.dev/cl/752182"
        },
        {
          "url": "https://go.dev/issue/77952"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/EdhZqrQ98hk"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-4599"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Jakub Ciolek"
        }
      ]
    }
  }
}