---
id: "CVE-2026-118732"
page: "https://infrastack.ai/live/CVE-2026-118732"
kind: "vulnerability"
aliases: ["CVE-2026-118732"]
title: "Microsoft Excel: use-after-free lets a remote attacker run code"
severity: "high"
cvss: 8.8
epss: null
exploited: false
status: "open"
category: "package"
products: [{"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"}, {"name": "Office for Mac (365, LTSC 2021, LTSC 2024)", "fixed": ["16.115.26110837"], "affected": "< 16.115.26110837", "ecosystem": "vendor"}, {"name": "Office Online Server", "fixed": ["16.0.10417.20236"], "affected": ">= 16.0.0.0, < 16.0.10417.20236", "ecosystem": "vendor"}, {"name": "Microsoft 365 Apps for Enterprise", "fixed": [], "affected": ">= 16.0.1, see https://aka.ms/OfficeSecurityReleases", "ecosystem": "vendor"}]
ecosystems: []
tags: ["excel", "macos", "microsoft-office", "office-online-server", "package", "user-interaction", "windows"]
not_affected_if: ["patched-build"]
published_at: "2026-11-10T19:19:49+00:00"
first_seen_at: "2026-11-10T19:24:54+00:00"
updated_at: "2026-11-10T23:00:40+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118732", "first_seen_at": "2026-11-10T19:24:54+00:00"}, {"source": "analyst", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118732", "first_seen_at": "2026-11-10T23:00:40+00:00", "cites": ["https://nvd.nist.gov/vuln/detail/CVE-2026-118732"]}]
exploit_sources: []
---

# Microsoft Excel: use-after-free lets a remote attacker run code

Link for people: https://infrastack.ai/live/CVE-2026-118732 (this .md is for agents)

A memory bug in Microsoft Office Excel lets a use-after-free condition be triggered over a network. An unauthorized attacker could use it to execute code on the victim's machine.

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

## Affected

- 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
- vendor:Office for Mac (365, LTSC 2021, LTSC 2024) affected < 16.115.26110837 fixed 16.115.26110837
- vendor:Office Online Server affected >= 16.0.0.0, < 16.0.10417.20236 fixed 16.0.10417.20236
- vendor:Microsoft 365 Apps for Enterprise affected >= 16.0.1, see https://aka.ms/OfficeSecurityReleases fixed no fixed version listed

## How to check

In Excel: File > Account > About Excel and compare the build to the fixed versions. Mac: Excel > About Excel. Office Online Server: check the installed version. Builds below the fixed ones are affected.

## Fix

Update to a fixed build: Microsoft 365 Apps per https://aka.ms/OfficeSecurityReleases; Office LTSC 2021 16.0.14334.21048; Office LTSC 2024 16.0.17932.21140; Office for Mac (365, LTSC 2021/2024) 16.115.26110837; Office Online Server 16.0.10417.20236.

## Timeline

- 2026-11-10T19:24:54+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-118732
- 2026-11-10T23:00:40+00:00 analyst https://nvd.nist.gov/vuln/detail/CVE-2026-118732 — MSRC page is JS-only (empty); affected/fixed builds taken from Microsoft CNA data on NVD. Nothing verified (secondary page). Not exploited per sources; UI:R so a user must open a crafted file.

## Documents

- [describes] NVD CVE-2026-118732 (Microsoft CNA data) https://nvd.nist.gov/vuln/detail/CVE-2026-118732

## From the sources

Use after free in Microsoft Office Excel 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_