KB4462915: Windows Server Security Update (October 2018)
Microsoft Windows Win32k contains a vulnerability that allows an attacker to escalate privileges.
A local attacker, without authentication, 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 2022-07-21 under CISA BOD 22-01.
This vulnerability affects Microsoft Win32k. An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers. Exploitation requires local access, low attack complexity, no authentication required, and user interaction required.
Probably yes if any of these apply:
Used in known ransomware campaigns. Threat-research write-up: http://packetstormsecurity.com/files/153669/Microsoft-Windows-NtUserSetWindowFNID-Win32k-User-Callback.html
Manual download
For air-gapped servers or out-of-band deployment. Microsoft Update Catalog returns every OS-version variant of this update.
↗ Microsoft Update CatalogKB4462915Manual remediation steps
Apply the Microsoft Security Update
Microsoft has released an official security update that fixes this vulnerability.
Required KB Updates
Supersedes: KB4457128, KB4457129, KB4457131, KB4457132, KB4457135, KB4457138, KB4457142, KB4457144, KB4458010
Affected Products
Installation Methods
Windows Update (recommended)
Microsoft Update Catalog (manual download)
.msu installer with administrator privilegesWSUS / SCCM / Intune
Approve KB4462915 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 @('KB4462915','KB4462917','KB4462918','KB4462919','KB4462922','KB4462923','KB4462926','KB4462929','KB4462931','KB4462937','KB4462941','KB4463097','KB4463104','KB4464330') }
References
Discovery Credit
Kaspersky Lab
No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.