Out-of-bounds Read in Microsoft Office 365 For Mac
CVE-2026-56176
Out-of-bounds read in Windows Win32K - GRFX allows an authorized attacker to elevate privileges locally.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (25.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Microsoft Office 365 For Mac
- Microsoft Office For Android
- Microsoft Office Ltsc For Mac 2021
- Microsoft Office Ltsc For Mac 2024
- Microsoft Windows 10 1607
- Microsoft Windows 10 1809
- Microsoft Windows 10 21h2
- Microsoft Windows 10 22h2
- Microsoft Windows 10 Version 1607 — versions 10.0.14393.0
- Microsoft Windows 10 Version 1809 — versions 10.0.17763.0
Weakness classification (CWE)
References
- Windows Win32k Elevation of Privilege Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-56176?
- CVE-2026-56176 is a high-severity vulnerability in Microsoft Office 365 For Mac, classified under Out-of-bounds Read. CVSS score: 7.8/10. Published 2026-07-14.
- How severe is CVE-2026-56176?
- High severity. CVSS v3 base score is 7.8 out of 10.