Deserialization in Microsoft 365 Apps
CVE-2025-21364
Microsoft Excel Security Feature Bypass Vulnerability
Vulnerability class: Insecure Deserialization
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.016 (74.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 74.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000
Affected products
- Microsoft 365 Apps
- Microsoft 365 Apps For Enterprise — versions 16.0.1
- Microsoft Office Ltsc 2024 — versions 16.0.0
- Microsoft Office Long Term Servicing Channel — versions 2024
Weakness classification (CWE)
References
- msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21364 (vendor-advisory, Patch, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2025-21364?
- CVE-2025-21364 is a high-severity vulnerability in Microsoft 365 Apps, classified under Deserialization of Untrusted Data. CVSS score: 7.8/10. Published 2025-01-14.
- How severe is CVE-2025-21364?
- High severity. CVSS v3 base score is 7.8 out of 10.