CVE tracker / CVE-2026-64918
CVE-2026-64918
CVE-2026-64918 is the Microsoft Office Spoofing Vulnerability. Microsoft rates it Important, CVSS 6.5. It is not in CISA's Known Exploited Vulnerabilities catalog. Published September 8, 2026.
Risk summary
MediumSpoofing
6.5
CVSS v3 base
0.9%
EPSS: chance of exploitation in 30 days
Medium
Severity
Important
Microsoft's rating
Less Likely
Microsoft: exploitation
No
In CISA KEV
Microsoft describes it: “Insufficiently protected credentials in Microsoft Office allows an unauthorized attacker to perform spoofing over a network.”
How to fix it
Microsoft lists 6 affected products and the update that fixes each:
- KB5002916 · fixed build 16.0.5569.1003
Microsoft Office 2016 (64-bit edition), Microsoft Office 2016 (32-bit edition) - Click to Run · fixed build https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editions, Microsoft Office 2019 for 32-bit editions - Release Notes · fixed build https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 64-bit Systems, Microsoft 365 Apps for Enterprise for 32-bit Systems
What Microsoft changed
- September 8, 2026: Information published.
Details
- Weakness
- CWE-522: Insufficiently Protected Credentials
- Publicly disclosed (Microsoft)
- No
- Exploited (Microsoft)
- No
- Known exploited (CISA KEV)
- Not listed
- Published
- September 8, 2026
- Last revised
- September 8, 2026
Get told when this changes
Senserva Watch emails Microsoft security and patch alerts when something moves: a new exploitation report, a revised fix, a known issue. Free, one email address.
References
From Microsoft, CISA, NVD and FIRST data; the Microsoft details were read when this page was opened. Check the references above before you act.