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Δ / VULNERABILITY RECORD

CVE-2026-21260.

Source-reported disclosure and enrichment record.

SEVERITY / CVSSHIGH / 7.5No severity score in this snapshot.
EXPLOITATION STATUSNot listed in the cached KEV catalogThis does not establish absence of exploitation.
RECORD STATUSMicrosoft vendor recordModified Feb 10, 2026

Disclosure summary

Exposure of sensitive information to an unauthorized actor in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.

Source-reported weakness categories

CWE-200

Source-specific records & product guidance

Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.

Microsoft Security Updates (CVRF) · 2026-Feb

Open original source · Updated Feb 10, 2026

Microsoft Outlook Spoofing Vulnerability

Maximum of vendor-reported product scores; products and fixed builds are associations, not a universal affected-version statement.

Microsoft maximum product score: 7.5

VendorProduct / associationVersion / bounds
Microsoft update guideMicrosoft SharePoint Enterprise Server 2016 (MSRC status code 3)
Microsoft update guideMicrosoft SharePoint Server 2019 (MSRC status code 3)
Microsoft update guideMicrosoft Office 2019 for 32-bit editions (MSRC status code 3)
Microsoft update guideMicrosoft Office 2019 for 64-bit editions (MSRC status code 3)
Microsoft update guideMicrosoft 365 Apps for Enterprise for 32-bit Systems (MSRC status code 3)
Microsoft update guideMicrosoft 365 Apps for Enterprise for 64-bit Systems (MSRC status code 3)
Microsoft update guideMicrosoft Office LTSC 2021 for 64-bit editions (MSRC status code 3)
Microsoft update guideMicrosoft Office LTSC 2021 for 32-bit editions (MSRC status code 3)
Microsoft update guideMicrosoft SharePoint Server Subscription Edition (MSRC status code 3)
Microsoft update guideMicrosoft Office LTSC 2024 for 32-bit editions (MSRC status code 3)
Microsoft update guideMicrosoft Office LTSC 2024 for 64-bit editions (MSRC status code 3)
Microsoft update guideMicrosoft Outlook 2016 (32-bit edition) (MSRC status code 3)
Microsoft update guideMicrosoft Outlook 2016 (64-bit edition) (MSRC status code 3)

Vendor remediation references

  • 5002841 · build 16.0.5539.1002 · product IDs 10950
  • Vendor guidance · product IDs 10950
  • 5002840 · build 16.0.5539.1002 · product IDs 10950
  • Vendor guidance · product IDs 10950
  • 5002834 · build 16.0.10417.20097 · product IDs 11585
  • Vendor guidance · product IDs 11585
  • 5002836 · build 16.0.10417.20097 · product IDs 11585
  • Vendor guidance · product IDs 11585
  • Click to Run · build https://aka.ms/OfficeSecurityReleases · product IDs 11573, 11574, 11762, 11763, 11952, 11953, 12420, 12421
  • Vendor guidance · product IDs 11573, 11574, 11762, 11763, 11952, 11953, 12420, 12421
  • 5002833 · build 16.0.19127.20518 · product IDs 11961
  • Vendor guidance · product IDs 11961
  • 5002839 · build 16.0.5539.1002 · product IDs 10765, 10766
  • Vendor guidance · product IDs 10765, 10766

Original records & references

PUBLISHED 2026-02-10T03:00:00-05:00
MODIFIED 2026-02-10T03:00:00-05:00
INGESTED 2026-10-08T12:45:17-04:00