CVE-2021-31955

CVE-2021-31955 is a medium-severity (CVSS 5.5) vulnerability in Microsoft Windows. 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 November 17, 2021. CISA does not currently list it as used in ransomware campaigns. Microsoft has 390 vulnerabilities in the KEV catalog, 117 of them linked to ransomware.

Windows Kernel Information Disclosure Vulnerability

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

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31955
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31955
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31955