CVE-2021-26900: Microsoft Windows CInteractionTrackerMarshaler Use-After-Free Privilege Escalation Vulnerability
Windows Win32k Elevation of Privilege Vulnerability
Other sources
This vulnerability allows local attackers to escalate privileges 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 DirectComposition. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the kernel.
— 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 10.0.19043.867Patch KB5000802 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.18363.1440Patch KB5000808
Event History
Frequently Asked Questions
What is the severity of CVE-2021-26900?
CVE-2021-26900 has a severity rating of 'Important' as it allows local attackers to escalate privileges.
How do I fix CVE-2021-26900?
To mitigate CVE-2021-26900, apply the latest security updates provided by Microsoft for the affected versions of Windows.
Which Windows versions are affected by CVE-2021-26900?
CVE-2021-26900 affects Windows 10 versions 20H2, 1909, 2004, and Windows Server 2016 versions 20H2 and 1909.
Can CVE-2021-26900 be exploited remotely?
No, CVE-2021-26900 requires local access to the computer to exploit the vulnerability.
What type of vulnerability is CVE-2021-26900?
CVE-2021-26900 is classified as an Elevation of Privilege vulnerability.