---
id: "CVE-2026-110055"
page: "https://infrastack.ai/live/CVE-2026-110055"
kind: "vulnerability"
aliases: ["CVE-2026-110055"]
title: "Microsoft Word: heap buffer overflow lets a remote attacker run code"
severity: "high"
cvss: 8.8
epss: null
exploited: false
status: "open"
category: "other"
products: [{"name": "Microsoft Office LTSC 2021", "fixed": ["16.0.14334.21048"], "affected": "< 16.0.14334.21048", "ecosystem": "vendor"}, {"name": "Microsoft Office LTSC 2024", "fixed": ["16.0.17932.21140"], "affected": "< 16.0.17932.21140", "ecosystem": "vendor"}, {"name": "Microsoft Office for Mac", "fixed": ["16.115.26110837"], "affected": "< 16.115.26110837", "ecosystem": "vendor"}, {"name": "Microsoft 365 Apps for Enterprise", "fixed": [], "affected": "16.0.1 < see aka.ms/OfficeSecurityReleases", "ecosystem": "vendor"}]
ecosystems: []
tags: ["macos", "microsoft-office", "other", "user-interaction", "windows", "word"]
not_affected_if: []
published_at: "2026-11-10T19:18:23+00:00"
first_seen_at: "2026-11-10T19:24:27+00:00"
updated_at: "2026-11-11T00:35:26+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110055", "first_seen_at": "2026-11-10T19:24:27+00:00"}, {"source": "analyst", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110055", "first_seen_at": "2026-11-11T00:35:26+00:00", "cites": ["https://nvd.nist.gov/vuln/detail/CVE-2026-110055"]}]
exploit_sources: []
---

# Microsoft Word: heap buffer overflow lets a remote attacker run code

Link for people: https://infrastack.ai/live/CVE-2026-110055 (this .md is for agents)

Heap-based buffer overflow in Microsoft Office Word (CWE-122) lets an attacker run code on the victim's machine. Microsoft rates it CVSS 8.8 (network, low complexity, no privileges, user interaction required), so a user probably has to open a crafted file. Microsoft's CNA data lists fixed builds; no exploitation reported in the sources read.

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

## Affected

- vendor:Microsoft Office LTSC 2021 affected < 16.0.14334.21048 fixed 16.0.14334.21048
- vendor:Microsoft Office LTSC 2024 affected < 16.0.17932.21140 fixed 16.0.17932.21140
- vendor:Microsoft Office for Mac affected < 16.115.26110837 fixed 16.115.26110837
- vendor:Microsoft 365 Apps for Enterprise affected 16.0.1 < see aka.ms/OfficeSecurityReleases fixed no fixed version listed

## How to check

In Word, File > Account > About Word and compare the build: Office LTSC 2021 needs 16.0.14334.21048 or later; Office LTSC 2024 needs 16.0.17932.21140 or later; Office for Mac (365, LTSC 2021, LTSC 2024) needs 16.115.26110837 or later; Microsoft 365 Apps need the current build from https://aka.ms/OfficeSecurityReleases.

## Fix

Update Office to the fixed build: LTSC 2021 16.0.14334.21048, LTSC 2024 16.0.17932.21140, Office for Mac 16.115.26110837, Microsoft 365 Apps: current build per aka.ms/OfficeSecurityReleases. Not confirmed on the MSRC page.

## Timeline

- 2026-11-10T19:24:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-110055
- 2026-11-11T00:35:26+00:00 analyst https://nvd.nist.gov/vuln/detail/CVE-2026-110055 — NVD carries Microsoft CNA data (affected builds, CVSS 8.8 UI:R). MSRC Update Guide page is JS-only and unreadable, CVRF API gave nothing, so nothing marked verified; no exploitation or PoC info found.

## Documents

- [describes] NVD CVE-2026-110055 (Microsoft CNA data) https://nvd.nist.gov/vuln/detail/CVE-2026-110055

## From the sources

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.

---

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