Windows ALPC heap overflow allows privilege escalation

high severity · exploited in the wild · published 2026-09-08

A heap-based buffer overflow in Windows Advanced Local Procedure Call lets an attacker raise their privileges locally. It is already being exploited in the wild.

Fixed in: 10.0.20348.5622

CVE: CVE-2026-85880

Source: Microsoft (MSRC)

Am I affected?

You are affected if the installed version is older than 10.0.20348.5622. Check the version you have and update to 10.0.20348.5622 or later. The fixed version is verified against a vendor or advisory source.

Get the fix

FixLane has a reviewed fix procedure for this incident: a read-only check first, then the fix. Ask the Telegram bot, or connect an AI agent to the FixLane MCP server and call get_fix_prompt with incident id 1867 and your operating system.