CVEs / CVE-2021-31955
CVE-2021-31955: Microsoft Windows Kernel Information Disclosure Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- low 2.1 CVSS 2.0 (NVD)
- EPSS 81.1% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
Description
Windows Kernel Information Disclosure Vulnerability
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows 10 Version 1809 | from 10.0.0, before 10.0.17763.1999 | 10.0.17763.1999 |
| Microsoft Windows Server 2019 | from 10.0.0, before 10.0.17763.1999 | 10.0.17763.1999 |
| Microsoft Windows Server 2019 (Server Core installation) | from 10.0.0, before 10.0.17763.1999 | 10.0.17763.1999 |
| Microsoft Windows 10 Version 1909 | from 10.0.0, before 10.0.18363.1621 | 10.0.18363.1621 |
| Microsoft Windows 10 Version 21H1 | from 10.0.0, before 10.0.19043.1052 | 10.0.19043.1052 |
| Microsoft Windows 10 Version 2004 | from 10.0.0, before 10.0.19041.1052 | 10.0.19041.1052 |
| Microsoft Windows Server version 2004 | from 10.0.0, before 10.0.19041.1052 | 10.0.19041.1052 |
| Microsoft Windows 10 Version 20H2 | from 10.0.0, before 10.0.19042.1052 | 10.0.19042.1052 |
| Microsoft Windows Server version 20H2 | from 10.0.0, before 10.0.19042.1052 | 10.0.19042.1052 |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 17 Nov 2021 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 2.0 | 2.1 lowAV:L/AC:L/Au:N/C:P/I:N/A:NScored by NVD |
|---|---|
| Weakness | CWE-497 |
References
- CVE-2021-31955 on NVD
- CVE-2021-31955 in the CISA KEV catalog
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31955 Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31955 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.