CVE-2026-89134 (GCVE-0-2026-89134)

Vulnerability from cvelistv5 – Published: 2026-09-27 09:16 – Updated: 2026-09-27 09:16
VLAI
Title
Subject CN name-constraint check bypassed when non-DNS SAN present
Summary
A certificate with no dNSName SAN but another SAN type present (e.g. registeredID or iPAddress) bypassed the Subject CN dNSName name-constraint check. The CN-as-DNS fallback was gated on cert->subjectCN != NULL && cert->altNames == NULL && !cert->isCA instead of "no dNSName SAN", so an out-of-scope CN was accepted. This incomplete fix from CVE-2026-6731, leading to the name-constraint check issue, was introduced in wolfSSL version 5.9.2.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Vendor Product Version CPE status
wolfSSL wolfSSL Affected: 5.9.2 (semver)
guessed Create a notification for this product.
Date Public
2026-09-26 12:00
Credits
Jorge Milla (Pig-Tail)
Show details on NVD website
To clipboard 

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          ],
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        }
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            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
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        "shortName": "wolfSSL"
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      "references": [
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          "url": "https://github.com/wolfSSL/wolfssl/pull/10837"
        }
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      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Subject CN name-constraint check bypassed when non-DNS SAN present",
      "x_generator": {
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  "cveMetadata": {
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    "cveId": "CVE-2026-89134",
    "datePublished": "2026-09-27T09:16:58.067Z",
    "dateReserved": "2026-09-10T22:37:22.616Z",
    "dateUpdated": "2026-09-27T09:16:58.067Z",
    "state": "PUBLISHED"
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      "percentile": "0.02743"
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        "descriptions": [
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            "value": "A certificate with no dNSName SAN but another SAN type present (e.g. registeredID or iPAddress) bypassed the Subject CN dNSName name-constraint check. The CN-as-DNS fallback was gated on cert-\u003esubjectCN != NULL \u0026\u0026 cert-\u003ealtNames == NULL \u0026\u0026 !cert-\u003eisCA instead of \"no dNSName SAN\", so an out-of-scope CN was accepted. This incomplete fix from CVE-2026-6731, leading to the name-constraint check issue, was introduced in wolfSSL version 5.9.2."
          }
        ],
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        "lastModified": "2026-09-28T20:47:20.760",
        "metrics": {
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                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
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                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
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                "userInteraction": "NONE",
                "valueDensity": "NOT_DEFINED",
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        "vulnStatus": "Awaiting Analysis",
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}



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