VDB
MSRC_CVE-2026-21509
MSRC_CVE-2026-21509
PUBLISHED
CVSS 7.800000190734863 HIGH
Risk Scores
CVSS v3.1
7.800000190734863
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Microsoft Office LTSC 2021 for 64-bit editions https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office 2016 (32-bit edition) <16.0.5539.1001 | ||
| Microsoft Office LTSC 2024 for 64-bit editions <https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office 2016 (64-bit edition) <16.0.5539.1001 | ||
| Microsoft 365 Apps for Enterprise for 64-bit Systems https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office 2019 for 64-bit editions <16.0.10417.20095 | ||
| Microsoft Office LTSC 2024 for 32-bit editions https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office LTSC 2021 for 32-bit editions <https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office 2019 for 64-bit editions 16.0.10417.20095 | ||
| Microsoft Office 2016 (64-bit edition) 16.0.5539.1001 | ||
| Microsoft Office 2016 (32-bit edition) 16.0.5539.1001 | ||
| Microsoft 365 Apps for Enterprise for 32-bit Systems https://aka.ms/OfficeSecurityReleases | ||
| Microsoft 365 Apps for Enterprise for 64-bit Systems <https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office 2019 for 32-bit editions <16.0.10417.20095 | ||
| Microsoft Office LTSC 2024 for 64-bit editions https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office LTSC 2024 for 32-bit editions <https://aka.ms/OfficeSecurityReleases | ||
| Microsoft 365 Apps for Enterprise for 32-bit Systems <https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office 2019 for 32-bit editions 16.0.10417.20095 | ||
| Microsoft Office LTSC 2021 for 64-bit editions <https://aka.ms/OfficeSecurityReleases | ||
| Microsoft Office LTSC 2021 for 32-bit editions https://aka.ms/OfficeSecurityReleases |
Timeline
- Jan 13, 2026 CVE Published
- Jan 29, 2026 CVE Updated
- Apr 29, 2026 Security Advisory
- Apr 29, 2026 Security Advisory
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21509 advisory
- https://msrc.microsoft.com/csaf/advisories/2026/msrc_cve-2026-21509.json advisory
- https://www.microsoft.com/en-us/msrc/exploitability-index?rtc=1 url
- https://support.microsoft.com/lifecycle url
- https://www.first.org/cvss url
- https://learn.microsoft.com/en-us/officeupdates/update-history-office-2019 fix
- https://docs.microsoft.com/en-us/officeupdates/office365-proplus-security-updates fix
- https://support.microsoft.com/help/5002713 fix