CVE-2026-43820

{
  "id": "CVE-2026-43820",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-23T15:17:05.503",
  "lastModified": "2026-10-24T13:10:00.147",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "NIOSSLCertificate._subjectAlternativeNames provides access to the raw bytes for a cert's SANs. NIOSSL provides access to a buffer assumed to be backed by an ASN1_STRING, but not all SANs are backed by ASN1_STRING, so accessing the buffer for such a type can lead to out-of-bounds memory access. This vulnerability is addressed in swift-nio-ssl version 2.37.2."
    },
    {
      "lang": "es",
      "value": "NIOSSLCertificate._subjectAlternativeNames proporciona acceso a los bytes sin procesar de los SAN de un certificado. NIOSSL proporciona acceso a un búfer que se asume que está respaldado por un ASN1_STRING, pero no todos los SAN están respaldados por un ASN1_STRING, por lo que acceder al búfer para dicho tipo puede llevar a un acceso a memoria fuera de límites. Esta vulnerabilidad se aborda en swift-nio-ssl versión 2.37.2."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Apple",
          "product": "swift-nio-ssl",
          "versions": [
            {
              "version": "0",
              "lessThan": "2.37.2",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
          "baseScore": 7.7,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 5.2
      }
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    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-24T20:09:17.611102Z",
          "id": "CVE-2026-43820",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
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          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:apple:swiftnio_ssl:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "2.18.0",
              "versionEndExcluding": "2.37.2",
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  "references": [
    {
      "url": "https://github.com/apple/swift-nio-ssl/security/advisories/GHSA-xfxg-9975-pc2j",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory",
        "Exploit"
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      "tags": [
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}