KB4517389: Windows Server Security Update (October 2019)
A privilege escalation vulnerability exists when Windows Error Reporting manager improperly handles hard links. An attacker who successfully exploited this vulnerability could overwrite a targeted file leading to an elevated status.
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 2022-04-05 under CISA BOD 22-01.
This is a Software Vulnerability (CWE-59) (CWE-59) vulnerability in Microsoft Windows. An elevation of privilege vulnerability exists when Windows Error Reporting manager improperly handles hard links, aka 'Windows Error Reporting Manager Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-1339, CVE-2019-1342. Exploitation requires local access, low 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 2022-03-15; federal agencies required to remediate by 2022-04-05.
Manual download
For air-gapped servers or out-of-band deployment. Microsoft Update Catalog returns every OS-version variant of this update.
↗ Microsoft Update CatalogKB4517389Manual remediation steps
Apply the Microsoft Security Update
Microsoft has released an official security update that fixes this vulnerability.
Required KB Updates
Supersedes: KB4516026, KB4524147, KB4524148, KB4524149, KB4524150, KB4524151, KB4524152, KB4524153, KB4524154, KB4524156, KB4524157
Affected Products
Installation Methods
Windows Update (recommended)
Microsoft Update Catalog (manual download)
.msu installer with administrator privilegesWSUS / SCCM / Intune
Approve KB4517389 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 @('KB4517389','KB4519338','KB4519976','KB4519985','KB4519990','KB4519998','KB4520002','KB4520003','KB4520004','KB4520005','KB4520007','KB4520008','KB4520009','KB4520010','KB4520011') }
References
Discovery Credit
David Cash of NCC Group, Clément Lavoillotte @clavoillotte of Almond
No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.