CVE-2026-109454

Critical (9)—

Schedule the patchSeverity Critical 9. No public exploit or active exploitation known.

Severity9Critical · CVSS 3.1

Exploitation probability0.84 %higher than 58% of CVEs · score from Nov 11, 2026

Active exploitationNonot in the CISA catalog · checked Nov 12, 03:00 AM

Public exploitNot knownno public code found

News and reports on Orbitaley

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.

Timeline

Built from our own data: NVD, CISA KEV and other exploitation catalogues, FIRST EPSS, public exploits, specialised media and Orbitaley coverage.

Nov 10, 2026CVE record published in NVD
Nov 10, 2026First mention in specialised media (NCSC-NL)
Nov 10, 2026Alert: Microsoft fixes 200 vulnerabilities, including an Outlook flaw CISA confirms is being exploited

Media coverage

Specialised security media that have cited this CVE:

NCSC-NL · NCSC-2026-0474 [1.00] [M/H] Kwetsbaarheden verholpen in Microsoft Office (Nov 10, 2026)

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1189 Drive-by Compromiseinitial access90 %

CWE-79 (XSS) con UI:R y AV:N implica drive-by en el navegador; el texto menciona spoofing, y la ejecución de JavaScript es inherente a XSS, no declarada explícitamente.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

User Training Restrict Web-Based Content Application Isolation and Sandboxing Exploit Protection Update Software

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Microsoft — Office Sharepoint^AI

NVD record

NVD status: Awaiting Analysis
Published: Nov 10, 2026
Last modified: Nov 10, 2026
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
Weakness (CWE): CWE-79

References

Referencemsrc.microsoft.com/update-guide/vulnerability/CVE-2026-109454

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-109454",
  "cveTags": [],
  "metrics": {
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      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-109454",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-11-10T20:52:52.638507Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "secure@microsoft.com",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 9,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 6,
        "exploitabilityScore": 2.3
      }
    ]
  },
  "affected": [
    {
      "source": "secure@microsoft.com",
      "affectedData": [
        {
          "vendor": "Microsoft",
          "product": "Microsoft SharePoint Server Subscription Edition",
          "versions": [
            {
              "status": "affected",
              "version": "16.0.0",
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          ],
          "platforms": [
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  "published": "2026-11-10T19:18:14.347",
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-109454",
      "source": "secure@microsoft.com"
    }
  ],
  "vulnStatus": "Awaiting Analysis",
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  ],
  "lastModified": "2026-11-10T21:18:04.087",
  "sourceIdentifier": "secure@microsoft.com"
}