MSRC_CVE-2026-33999

Vulnerability from csaf_microsoft - Published: 2026-04-02 00:00 - Updated: 2026-05-06 14:43
Summary
Xorg: xwayland: x.org x server: denial of service via integer underflow in xkb compatibility map handling
Notes
Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
CVE-2026-33999
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-191 - Integer Underflow (Wrap or Wraparound)
Affected products
Product Identifier Version Remediation
Unresolved product id: 21247-17084 —
Unresolved product id: 21316-17084 —
Product Identifier Version Remediation
Unresolved product id: 17086-3 —
None Available
Unresolved product id: 17084-2 —
Vendor Fix fix
Unresolved product id: 17084-1 —
Vendor Fix fix
References
To clipboard 

{
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      "tlp": {
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        "url": "https://www.first.org/tlp/"
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    "notes": [
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        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
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      "name": "Microsoft Security Response Center",
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    "references": [
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        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-33999.json"
      },
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      },
      {
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        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "Xorg: xwayland: x.org x server: denial of service via integer underflow in xkb compatibility map handling",
    "tracking": {
      "current_release_date": "2026-05-06T14:43:53.000Z",
      "generator": {
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  "vulnerabilities": [
    {
      "cve": "CVE-2026-33999",
      "cwe": {
        "id": "CWE-191",
        "name": "Integer Underflow (Wrap or Wraparound)"
      },
      "notes": [
        {
          "category": "general",
          "text": "redhat",
          "title": "Assigning CNA"
        }
      ],
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          "21316-17084"
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        {
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          "summary": "CVE-2026-33999 Xorg: xwayland: x.org x server: denial of service via integer underflow in xkb compatibility map handling - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-33999.json"
        }
      ],
      "remediations": [
        {
          "category": "none_available",
          "date": "2026-04-29T01:11:14.000Z",
          "details": "There is no fix available for this vulnerability as of now",
          "product_ids": [
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          ]
        },
        {
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          "date": "2026-04-29T01:11:14.000Z",
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          "product_ids": [
            "17084-2",
            "17084-1"
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        }
      ],
      "scores": [
        {
          "cvss_v3": {
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            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "temporalScore": 7.8,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "17086-3",
            "17084-2",
            "17084-1"
          ]
        }
      ],
      "title": "Xorg: xwayland: x.org x server: denial of service via integer underflow in xkb compatibility map handling"
    }
  ]
}



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