CVE-2021-26892: Microsoft Windows EFI Partition Incorrect Authorization Denial-of-Service Vulnerability
Windows Extensible Firmware Interface Security Feature Bypass Vulnerability
Other sources
This vulnerability allows local attackers to create a denial-of-service condition on affected installations of Microsoft Windows. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the Windows kernel. The issue results from improper authorization logic when accessing files in the EFI partition. An attacker can leverage this vulnerability to create a denial-of-service condition on the system.
— ZDI
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.18363.1440Patch KB5000808 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19043.867Patch KB5000802 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.14393.4283Patch KB5000803 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.1817Patch KB5000822 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17134.2087Patch KB5000809
Event History
Frequently Asked Questions
What is the severity of CVE-2021-26892?
CVE-2021-26892 has a severity rating of important according to Microsoft.
How do I fix CVE-2021-26892?
To fix CVE-2021-26892, install the available patches from Microsoft for your affected Windows version.
What versions of Windows are affected by CVE-2021-26892?
CVE-2021-26892 affects various versions of Windows including Windows 10 versions 20H2, 1809, 1803, 1909, and Windows Server 2016 and 2019.
Can CVE-2021-26892 be exploited remotely?
No, CVE-2021-26892 can only be exploited locally by an attacker with access to the system.
What type of vulnerability is CVE-2021-26892?
CVE-2021-26892 is a security feature bypass vulnerability in the Windows Extensible Firmware Interface.