---
id: "CVE-2026-95951"
page: "https://infrastack.ai/live/CVE-2026-95951"
kind: "vulnerability"
aliases: ["CVE-2026-95951"]
title: "Windows Installer: heap overflow lets a local user gain higher privileges"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "Windows Installer", "fixed": ["10.0.14393.9688", "10.0.17763.9487", "10.0.19044.7846", "10.0.19045.7846", "10.0.22631.7711", "10.0.26100.9974", "10.0.26200.9974", "10.0.28000.3501", "10.0.26300.9974", "10.0.20348.5870", "10.0.26100.33822"], "affected": "Windows 10 1607/Server 2016 < 10.0.14393.9688; 1809/Server 2019 < 10.0.17763.9487; 10 21H2 < 10.0.19044.7846; 10 22H2 < 10.0.19045.7846; 11 23H2 < 10.0.22631.7711; 11 24H2 < 10.0.26100.9974; 11 25H2 < 10.0.26200.9974; 11 26H1 < 10.0.28000.3501; 11 26H2 < 10.0.26300.9974; Server 2022 < 10.0.20348.5870; Server 2025 < 10.0.26100.33822", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["infrastructure", "local-privilege-escalation", "windows", "windows-server"]
not_affected_if: ["no-local-accounts", "patched-build"]
published_at: "2026-11-10T19:21:47+00:00"
first_seen_at: "2026-11-10T19:25:24+00:00"
updated_at: "2026-11-10T20:20:43+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-95951", "first_seen_at": "2026-11-10T19:25:24+00:00"}, {"source": "analyst", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-95951", "first_seen_at": "2026-11-10T20:20:43+00:00", "cites": ["https://nvd.nist.gov/vuln/detail/CVE-2026-95951"]}]
exploit_sources: []
---

# Windows Installer: heap overflow lets a local user gain higher privileges

Link for people: https://infrastack.ai/live/CVE-2026-95951 (this .md is for agents)

Windows Installer has a heap-based buffer overflow that lets an authorized local user raise their privileges. An attacker who already has a local account can use it to gain more control of the machine.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Windows Installer affected Windows 10 1607/Server 2016 < 10.0.14393.9688; 1809/Server 2019 < 10.0.17763.9487; 10 21H2 < 10.0.19044.7846; 10 22H2 < 10.0.19045.7846; 11 23H2 < 10.0.22631.7711; 11 24H2 < 10.0.26100.9974; 11 25H2 < 10.0.26200.9974; 11 26H1 < 10.0.28000.3501; 11 26H2 < 10.0.26300.9974; Server 2022 < 10.0.20348.5870; Server 2025 < 10.0.26100.33822 fixed 10.0.14393.9688, 10.0.17763.9487, 10.0.19044.7846, 10.0.19045.7846, 10.0.22631.7711, 10.0.26100.9974, 10.0.26200.9974, 10.0.28000.3501, 10.0.26300.9974, 10.0.20348.5870, 10.0.26100.33822

## How to check

Run winver or '[System.Environment]::OSVersion.Version' and compare the build (10.0.x.y) with the fixed builds listed in the fix. Anything below the fixed build for your Windows version is exposed.

## Fix

Install the November 2026 Microsoft cumulative update that brings your OS to at least: Win10 1607/Server 2016 10.0.14393.9688; 1809/Server 2019 10.0.17763.9487; Win10 21H2 10.0.19044.7846; Win10 22H2 10.0.19045.7846; Win11 23H2 10.0.22631.7711; Win11 24H2 10.0.26100.9974; Win11 25H2 10.0.26200.9974; Win11 26H1 10.0.28000.3501; Win11 26H2 10.0.26300.9974; Server 2022 10.0.20348.5870; Server 2025 10.0.26100.33822. KB numbers: check the MSRC entry.

## Timeline

- 2026-11-10T19:25:24+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-95951
- 2026-11-10T20:20:43+00:00 analyst https://nvd.nist.gov/vuln/detail/CVE-2026-95951 — Builds read from NVD, which carries Microsoft's CNA affected list. MSRC page is JS-only and not read, so nothing is marked verified. KB numbers unknown. No exploitation or PoC seen.

## Documents

- [describes] NVD CVE-2026-95951 (Microsoft CNA data) https://nvd.nist.gov/vuln/detail/CVE-2026-95951

## From the sources

Heap-based buffer overflow in Windows Installer allows an authorized attacker to elevate privileges locally.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_