November 3, 2021 · Applied Cybernetics Group
CVE-2019-0859 — Microsoft Win32k
known ransomware use
Microsoft Win32k Privilege Escalation Vulnerability
- Added to KEV
2021-11-03- Federal due date
2022-05-03- Vendor
- Microsoft
- Product
- Win32k
- EPSS
- 90.3th percentile (score 0.042, as of
2026-09-16) - NVD CVSS v3.1
- —
- Ransomware use
- Known
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2019-0859
CISA short description
Microsoft Win32k fails to properly handle objects in memory causing privilege escalation. Successful exploitation allows an attacker to run code in kernel mode.
Required action
Apply updates per vendor instructions.