Windows Installer: Out-of-bounds read enables local privilege escalation

Summary

Microsoft has published CVE-2026-96060 for Windows Installer, the Windows component that installs, repairs and removes software. An out-of-bounds read (CWE-125) allows an authorized local user with low privileges to elevate their privileges to a higher level. The attacker must already have local access, for example through a compromised user account or malware running as a normal user. The CVSS base score is 7.8 (High), and NVD analysis was still pending at the time of research.

Affected

• Windows 10 Version 1607 and Windows Server 2016 (incl. Server Core): before 10.0.14393.9688
• Windows 10 Version 1809 and Windows Server 2019 (incl. Server Core): before 10.0.17763.9487
• Windows 10 Version 21H2: before 10.0.19044.7846
• Windows 10 Version 22H2: before 10.0.19045.7846 (from a third-party tracker, not confirmed in the CNA record)
• Windows 11 Version 23H2: before 10.0.22631.7711
• Windows 11 Version 24H2: before 10.0.26100.9974
• Windows 11 Version 25H2 and 26H2: before 10.0.26200.9974 and 10.0.26300.9974
• Windows 11 Version 26H1: before 10.0.28000.3501
• Windows Server 2022: before 10.0.20348.5870

Fixed in

• Fixed in the builds listed above (first fixed build per version).
• Verify the exact builds and KB numbers on the MSRC advisory before deployment.

Workaround

Unknown. No workaround or mitigation was found in the available sources. Apply the security update.

Exploitation

• Not known to be exploited in the wild.
• CISA SSVC assessment: exploitation none, not automatable, total technical impact.
• No public proof of concept found. Not listed in CISA KEV according to a third-party tracker.

Our recommendation

• Install the November 2026 security update on all affected Windows systems as part of the regular monthly cycle, and sooner on shared PCs, Remote Desktop and terminal servers.
• Check the MSRC advisory for the exact fixed builds and KB numbers.
• Identify and replace or isolate Windows 10 1607 and 1809 systems that are no longer supported.
• Restrict who can run installers on multi-user systems and monitor for unexpected privilege changes.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• Microsoft Security Update Guide: CVE-2026-96060 msrc.microsoft.com
• CVE Record CVE-2026-96060 www.cve.org
• Strix tracker: CVE-2026-96060 www.strix.ai
• Senserva: KB5131096 (November 2026 update) senserva.com

Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 02:42.