CVE-2018-8440 — Microsoft Windows Privilege Escalation Vulnerability

An elevation of privilege vulnerability exists when Windows improperly handles calls to Advanced Local Procedure Call (ALPC), aka "Windows ALPC Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Wi

01What is this vulnerability?

An elevation of privilege vulnerability exists when Windows improperly handles calls to Advanced Local Procedure Call (ALPC), aka "Windows ALPC Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

02Affected products

Vendor	Product	Versions
Microsoft	Windows 7	32-bit Systems Service Pack 1, x64-based Systems Service Pack 1
Microsoft	Windows Server 2012 R2	(Server Core installation)
Microsoft	Windows RT 8.1	Windows RT 8.1
Microsoft	Windows Server 2008	32-bit Systems Service Pack 2, 32-bit Systems Service Pack 2 (Server Core installation), Itanium-Based Systems Service Pack 2, x64-based Systems Service Pack 2, x64-based Systems Service Pack 2 (Server Core installation)
Microsoft	Windows Server 2012	(Server Core installation)
Microsoft	Windows 8.1	32-bit systems, x64-based systems
Microsoft	Windows Server 2016	(Server Core installation)
Microsoft	Windows Server 2008 R2	Itanium-Based Systems Service Pack 1, x64-based Systems Service Pack 1, x64-based Systems Service Pack 1 (Server Core installation)
Microsoft	Windows 10	32-bit Systems, Version 1607 for 32-bit Systems, Version 1607 for x64-based Systems, Version 1703 for 32-bit Systems, Version 1703 for x64-based Systems, Version 1709 for 32-bit Systems, Version 1709 for x64-based Systems, Version 1803 for 32-bit Systems, Version 1803 for x64-based Systems, x64-based Systems
Microsoft	Windows 10 Servers	version 1709 (Server Core Installation), version 1803 (Server Core Installation)

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2022-03-28. Ransomware use: Known.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2018-09-13T00:00:00.000Z
• Last modified: 2025-10-21T23:45:48.243Z
• Added to CISA KEV: 2022-03-28
• BOD 22-01 due: 2022-04-18

09References

• portal.msrc.microsoft.com — https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8440
• blog.0patch.com — https://blog.0patch.com/2018/09/comparing-our-micropatch-with.html
• blog.0patch.com — https://blog.0patch.com/2018/08/how-we-micropatched-publicly-dropped.html
• www.securitytracker.com — http://www.securitytracker.com/id/1041578
• www.securityfocus.com — http://www.securityfocus.com/bid/105153