CVE-2021-31955 : Windows Kernel Information Disclosure Vulnerability

Windows Kernel Information Disclosure Vulnerability

Published 2021-06-08 23:15:09

Updated 2024-07-29 17:34:01

Source Microsoft Corporation

View at NVD, CVE.org

Vulnerability category: Information leak

Products affected by CVE-2021-31955

Microsoft » Windows Server 2019
Versions before (<) 10.0.17763.1999
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows Server 2004
Versions before (<) 10.0.19041.1052
cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows 10 21h1
Versions before (<) 10.0.19043.1052
cpe:2.3:o:microsoft:windows_10_21h1:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows 10 1809
Versions before (<) 10.0.17763.1999
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows 10 20h2
Versions before (<) 10.0.19042.1052
cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows 10 1909
Versions before (<) 10.0.18363.1621
cpe:2.3:o:microsoft:windows_10_1909:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows 10 2004
Versions before (<) 10.0.19041.1052
cpe:2.3:o:microsoft:windows_10_2004:*:*:*:*:*:*:*:*
Matching versions
Microsoft » Windows Server 20h2
Versions before (<) 10.0.19042.1052
cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*
Matching versions

CVE-2021-31955 is in the CISA Known Exploited Vulnerabilities Catalog

CISA vulnerability name:

Microsoft Windows Kernel Information Disclosure Vulnerability

CISA required action:

Apply updates per vendor instructions.

CISA 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.

Notes:

https://nvd.nist.gov/vuln/detail/CVE-2021-31955

Added on 2021-11-03 Action due date 2021-11-17

Exploit prediction scoring system (EPSS) score for CVE-2021-31955

EPSS FAQ

1.37%

Probability of exploitation activity in the next 30 days EPSS Score History

~ 86 %

Percentile, the proportion of vulnerabilities that are scored at or less

CVSS scores for CVE-2021-31955

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source
2.1	LOW	AV:L/AC:L/Au:N/C:P/I:N/A:N	3.9	2.9	NIST
Access Vector: Local Access Complexity: Low Authentication: None Confidentiality Impact: Partial Integrity Impact: None Availability Impact: None
5.5	MEDIUM	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N	1.8	3.6	NIST
Attack Vector: Local Attack Complexity: Low Privileges Required: Low User Interaction: None Scope: Unchanged Confidentiality: High Integrity: None Availability: None
5.5	MEDIUM	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N	1.8	3.6	Microsoft Corporation
Attack Vector: Local Attack Complexity: Low Privileges Required: Low User Interaction: None Scope: Unchanged Confidentiality: High Integrity: None Availability: None

CWE ids for CVE-2021-31955

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Assigned by: nvd@nist.gov (Primary)
CWE-497 Exposure of Sensitive System Information to an Unauthorized Control Sphere

The product does not properly prevent sensitive system-level information from being accessed by unauthorized actors who do not have the same level of access to the underlying system as the product does.

Assigned by: 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

References for CVE-2021-31955

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31955

CVE-2021-31955 - Security Update Guide - Microsoft - Windows Kernel Information Disclosure Vulnerability
Patch;Vendor Advisory