CVE-2019-0859

CVE-2019-0859 is a high-severity (CVSS 7.8) vulnerability in Microsoft Win32k. CISA added it to the Known Exploited Vulnerabilities catalog on November 3, 2021, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by May 3, 2022. CISA also lists it as known to be used in ransomware campaigns, so it should be prioritised accordingly. Microsoft has 390 vulnerabilities in the KEV catalog, 117 of them linked to ransomware.

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0803.

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0859
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0859
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-0859