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CVE-2026-69402 Microsoft CVE debrief

Microsoft Office SharePoint Spoofing Vulnerability allows an authorized attacker to perform spoofing over a network due to improper neutralization of input during web page generation. This vulnerability has a CVSS score of 7.3 and is classified as HIGH severity. The vulnerability affects Microsoft SharePoint Server Subscription Edition deployments. Defenders responsible for these deployments should assess exposure and prioritize remediation efforts. The CVE Program record and NVD vulnerability detail provide official information on the vulnerability.

Vendor
Microsoft
Product
Microsoft SharePoint Server Subscription Edition
CVSS
HIGH 7.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-09-08
Original CVE updated
2026-10-08
Advisory published
2026-09-08
Advisory updated
2026-10-08

Who should care

Defenders responsible for Microsoft SharePoint Server Subscription Edition deployments should assess exposure and prioritize remediation efforts.

Why it matters

CVE-2026-69402 is a HIGH-severity spoofing vulnerability in Microsoft Office SharePoint that requires verification and patching to prevent exploitation.

  • Verify and apply patches to prevent exploitation.
  • Identify and inventory affected systems for remediation prioritization.
  • Monitor for suspicious activity related to Microsoft SharePoint Server Subscription Edition.

Technical summary

The vulnerability exists due to improper neutralization of input during web page generation in Microsoft Office SharePoint. An authorized attacker can exploit this to perform spoofing over a network. The vulnerability has a CVSS score of 7.3 and is classified as HIGH severity. Microsoft's advisory indicates a patch is available for Microsoft SharePoint Server Subscription Edition, specifically version 16.0.0 up to but not including 16.0.20326.20090.

Defensive priority

Defenders should prioritize verifying and applying patches for Microsoft SharePoint Server Subscription Edition, specifically version 16.0.0 up to but not including 16.0.20326.20090.

Recommended defensive actions

  • Verify and apply patches for Microsoft SharePoint Server Subscription Edition, specifically version 16.0.0 up to but not including 16.0.20326.20090.
  • Review and update inventory to ensure affected systems are identified and prioritized for remediation.
  • Monitor for suspicious activity related to Microsoft SharePoint Server Subscription Edition.

Evidence notes

The CVE Program record and NVD vulnerability detail provide official information on the vulnerability. Microsoft's advisory is referenced, indicating a patch is available.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-69402 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-69402

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-69402 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-69402

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Microsoft Office SharePoint Spoofing Vulnerability

    Unverified legacy reference

    URL: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/69xxx/CVE-2026-69402.json

    cve_program_cvelist_v5

  • Source reference

    Unverified legacy reference

    URL: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69402

    Supplemental source - vendor-advisory, patch

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.