CVE-2021-26866

Windows Update Service Elevation of Privilege Vulnerability

CVSS v3 7.1 HIGH
CVSS v2.0 3.6 LOW

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

3.6^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:N/I:P/A:P

Exploitability : 3.9 / Impact : 4.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26866	Patch Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-286/	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_10:-:::::::*
	cpe:2.3:o:microsoft:windows_10:20h2:::::::*
	cpe:2.3:o:microsoft:windows_10:1607:::::::*
	cpe:2.3:o:microsoft:windows_10:1803:::::::*
	cpe:2.3:o:microsoft:windows_10:1809:::::::*
	cpe:2.3:o:microsoft:windows_10:1909:::::::*
	cpe:2.3:o:microsoft:windows_10:2004:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:20h2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:1909:::::::*
	cpe:2.3:o:microsoft:windows_server_2016:2004:::::::*
	cpe:2.3:o:microsoft:windows_server_2019:-:::::::*

History

29 Dec 2023, 20:15

Type	Values Removed	Values Added
CVSS	v2 : ~~3.6~~ v3 : ~~6.1~~	v2 : 3.6 v3 : 7.1

03 May 2022, 16:04

Type	Values Removed	Values Added
CWE	~~CWE-269~~	CWE-59

Information

Published : 2021-03-11 16:15

Updated : 2024-02-04 21:23

NVD link : CVE-2021-26866

Mitre link : CVE-2021-26866

CVE.ORG link : CVE-2021-26866

JSON object : View

Products Affected

microsoft

windows_server_2019
windows_server_2016
windows_10

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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