Is CVE-2021-31955 in the CISA KEV catalog?

Yes. CVE-2021-31955 is on the CISA Known Exploited Vulnerabilities list, added 2021-11-03.

What is the CVSS severity of CVE-2021-31955?

CVE-2021-31955 has a CVSS v3 base score of 5.5 (MEDIUM).

What is the EPSS score for CVE-2021-31955?

CVE-2021-31955 has an EPSS score of 80.26% (100th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-31955

MEDIUMCISA KEVEPSS 100th pctl

5.5

CVSS v3

NVD

Description

Windows Kernel Information Disclosure Vulnerability

CWE-497

CVSS v3 Vector

Exploitability

Attack VectorLocal

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityNone

AvailabilityNone

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

Exploit Intelligence

80.26%probability of exploitation in 30 days

100thpercentile

Very high risk: more likely to be exploited than 100% of all known CVEs.

Known Exploited Vulnerability (CISA KEV)

Microsoft Windows Kernel Information Disclosure Vulnerability

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.

Apply updates per vendor instructions.

Remediation due: 2021-11-17

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-10-30.