FKIE_CVE-2026-21243

Vulnerability from fkie_nvd - Published: 2026-02-10 18:16 - Updated: 2026-02-11 20:41
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.
References
secure@microsoft.comhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21243Vendor Advisory
Impacted products
Vendor Product Version
microsoft windows_server_2019 *
microsoft windows_server_2022 *
microsoft windows_server_2022_23h2 *
microsoft windows_server_2025 *
To clipboard 

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      "nodes": [
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          "cpeMatch": [
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          "operator": "OR"
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network."
    }
  ],
  "id": "CVE-2026-21243",
  "lastModified": "2026-02-11T20:41:23.863",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
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        "impactScore": 3.6,
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        "type": "Secondary"
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  "published": "2026-02-10T18:16:25.480",
  "references": [
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      "source": "secure@microsoft.com",
      "tags": [
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      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21243"
    }
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  "sourceIdentifier": "secure@microsoft.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
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      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "secure@microsoft.com",
      "type": "Secondary"
    }
  ]
}


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  • 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.