CVE-2021-31955Actively exploitedAdded to KEV 2021-11-03

Microsoft Windows Kernel Information Disclosure Vulnerability

Microsoft, Windows

Description

Microsoft Windows Kernel contains an unspecified vulnerability that allows for information disclosure. Successful exploitation allows attackers to read the contents of kernel memory from a user-mode process.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

81.1%

estimated chance of real-world exploitation in the next 30 days, higher than 99.6% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

CWE-497

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