KB5039211: Windows Server Security Update (June 2024)
Microsoft Windows Kernel contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability that could allow for privilege escalation.
A local attacker, with a low-privilege account, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2024-11-05 under CISA BOD 22-01.
This is a Software Vulnerability (CWE-367) (CWE-367) vulnerability in Microsoft Windows. Windows Kernel Elevation of Privilege Vulnerability Exploitation requires local access, higher attack complexity, a low-privilege authenticated account, and no user interaction required.
Probably yes if any of these apply:
CISA confirms this CVE has been used in known ransomware campaigns. Added to the KEV catalog on 2024-10-15; federal agencies required to remediate by 2024-11-05.
Manual download
For air-gapped servers or out-of-band deployment. Microsoft Update Catalog returns every OS-version variant of this update.
↗ Microsoft Update CatalogKB5039211Manual remediation steps
Apply the Microsoft Security Update
Microsoft has released an official security update that fixes this vulnerability.
Required KB Updates
Supersedes: KB5037763, KB5037765, KB5037768, KB5037770, KB5037771, KB5037781, KB5037782, KB5037788, KB5037848
Affected Products
Fixed Build Numbers
Installation Methods
Windows Update (recommended)
Microsoft Update Catalog (manual download)
.msu installer with administrator privilegesWSUS / SCCM / Intune
Approve KB5039211 for the affected products in your update management console.
Microsoft Download Center Links
Verification
Confirm the update is installed:
Get-HotFix | Where-Object { $_.HotFixID -in @('KB5039211','KB5039212','KB5039213','KB5039214','KB5039217','KB5039225','KB5039227','KB5039236','KB5039330') }
References
Discovery Credit
Emma Kirkpatrick (@carrot_c4k3) working with Trend Micro Zero Day Initiative
No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.