Microsoft Windows: Privilege escalation through use-after-free in LLTD

Summary

A use-after-free flaw in the Windows Link Layer Topology Discovery (LLTD) component allows an authorized local attacker to elevate privileges. The attacker needs local access and a low-privilege account on the affected system, and attack complexity is high. Successful exploitation could give the attacker higher privileges on the system. Microsoft reports no known exploitation.

Affected

• Windows 10 Version 1607: builds before 10.0.14393.9688
• Windows 10 Version 1809: builds before 10.0.17763.9487
• Windows 10 Version 21H2: builds before 10.0.19044.7846
• Windows 10 Version 22H2: builds before 10.0.19045.7846
• Windows 11 Version 23H2: builds before 10.0.22631.7711
• Windows 11 Version 24H2: builds before 10.0.26100.9974
• Windows 11 Version 25H2: builds before 10.0.26200.9974
• Windows 11 Version 26H1: builds before 10.0.28000.3501
• Windows 11 Version 26H2: builds before 10.0.26300.9974
• Windows Server 2016 (including Server Core): builds before 10.0.14393.9688
• Windows Server 2019 (including Server Core): builds before 10.0.17763.9487
• Windows Server 2022: builds before 10.0.20348.5870

Fixed in

• Builds at or above the numbers listed above, according to the CVE record.
• KB article numbers: Unknown. Take them from the MSRC advisory. Verify build numbers there, as sources differ for some Windows 11 24H2 entries.

Workaround

• No vendor workaround known.
• Disabling LLTD is not confirmed as a mitigation. Apply the security update.

Exploitation

• Microsoft rates exploit code maturity as Unproven, and CISA SSVC lists exploitation as none.
• No public proof of concept or in-the-wild exploitation found at time of research.

Our recommendation

• Patch affected Windows 10, Windows 11 and Windows Server systems using the update from the MSRC advisory, prioritising shared and unmanaged machines.
• Check inventory for Windows 10 1607 and 1809 systems and confirm they still receive security updates; plan upgrades if they do not.
• Restrict local logon and standard user accounts on shared machines, and monitor for unexpected privilege changes or new local administrator accounts.

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

• CVE record (Microsoft CNA) www.cve.org
• MSRC Security Update Guide advisory msrc.microsoft.com
• LLTD background (Wikipedia) en.wikipedia.org
• LLTD policy CSP (Microsoft Learn) learn.microsoft.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, 08:57.