---
id: "CVE-2026-119997"
page: "https://infrastack.ai/live/CVE-2026-119997"
kind: "vulnerability"
aliases: ["CVE-2026-119997"]
title: "Microsoft Outlook: heap buffer overflow lets a local attacker run code"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "Microsoft 365 Apps for Enterprise", "fixed": ["see aka.ms/OfficeSecurityReleases"], "affected": ">= 16.0.1, below the build listed at aka.ms/OfficeSecurityReleases", "ecosystem": "vendor"}, {"name": "Microsoft Office LTSC 2021", "fixed": ["16.0.14334.21048"], "affected": ">= 16.0.1, < 16.0.14334.21048", "ecosystem": "vendor"}, {"name": "Microsoft Office LTSC 2024", "fixed": ["16.0.17932.21140"], "affected": ">= 16.0.0, < 16.0.17932.21140", "ecosystem": "vendor"}]
ecosystems: []
tags: ["microsoft-365", "microsoft-office", "office-ltsc", "outlook", "package", "windows"]
not_affected_if: ["outlook-web-only", "patched-nov-2026"]
published_at: "2026-11-10T19:20:25+00:00"
first_seen_at: "2026-11-10T19:25:07+00:00"
updated_at: "2026-11-10T22:08:13+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-119997", "first_seen_at": "2026-11-10T19:25:07+00:00"}, {"source": "analyst", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-119997", "first_seen_at": "2026-11-10T22:08:13+00:00", "cites": ["https://nvd.nist.gov/vuln/detail/CVE-2026-119997", "https://learn.microsoft.com/en-us/OfficeUpdates/microsoft365-apps-security-updates"]}]
exploit_sources: []
---

# Microsoft Outlook: heap buffer overflow lets a local attacker run code

Link for people: https://infrastack.ai/live/CVE-2026-119997 (this .md is for agents)

A heap-based buffer overflow in Microsoft Office Outlook lets an unauthorized attacker run code on the local machine. The sources do not describe the trigger file or action.

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

## Affected

- vendor:Microsoft 365 Apps for Enterprise affected >= 16.0.1, below the build listed at aka.ms/OfficeSecurityReleases fixed see aka.ms/OfficeSecurityReleases
- vendor:Microsoft Office LTSC 2021 affected >= 16.0.1, < 16.0.14334.21048 fixed 16.0.14334.21048
- vendor:Microsoft Office LTSC 2024 affected >= 16.0.0, < 16.0.17932.21140 fixed 16.0.17932.21140

## How to check

In Outlook: File > Office Account > About Outlook and compare the build with the fixed builds (LTSC 2021 16.0.14334.21048, LTSC 2024 16.0.17932.21140, Microsoft 365 Apps per aka.ms/OfficeSecurityReleases). Also check Office 2019/2021/2024 retail if you run them: Microsoft's CVE record does not list them, so confirm on the MSRC page.

## Fix

Update to the November 10, 2026 Office security update: Office LTSC 2021 build 16.0.14334.21048 or later, Office LTSC 2024 build 16.0.17932.21140 or later; Microsoft 365 Apps: current build per https://aka.ms/OfficeSecurityReleases (Current Channel 2610 build 20527.20196 or later per Microsoft's release notes).

## Timeline

- 2026-11-10T19:25:07+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-119997
- 2026-11-10T22:08:13+00:00 analyst https://nvd.nist.gov/vuln/detail/CVE-2026-119997 — Affected/fixed builds from Microsoft's CNA data via NVD; MSRC page not readable, so nothing marked verified. Not exploited per sources; BleepingComputer's exploited Outlook zero-day this Patch Tuesday is a different NTLM spoofing CVE. Trigger unknown.

## Documents

- [advisory] NVD CVE-2026-119997 (CNA Microsoft data) https://nvd.nist.gov/vuln/detail/CVE-2026-119997
- [fix] Release notes for Microsoft Office security updates (Nov 10, 2026 lists CVE-2026-110053 under Word) https://learn.microsoft.com/en-us/OfficeUpdates/microsoft365-apps-security-updates

## From the sources

Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code locally.

---

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