---
id: "CVE-2026-118716"
page: "https://infrastack.ai/live/CVE-2026-118716"
kind: "vulnerability"
aliases: ["CVE-2026-118716"]
title: "Microsoft Excel use-after-free allows remote code execution when a user opens a crafted file"
severity: "high"
cvss: 8.8
epss: null
exploited: false
status: "open"
category: "vendor"
products: [{"name": "Microsoft 365 Apps for Enterprise", "fixed": ["2610 20527.20196"], "affected": ">= 16.0.1, below the Nov 10 2026 build for your channel", "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"}, {"name": "Microsoft Office for Mac (365, LTSC 2021, LTSC 2024)", "fixed": ["16.115.26110837"], "affected": "< 16.115.26110837", "ecosystem": "vendor"}]
ecosystems: []
tags: ["desktop", "excel", "macos", "microsoft-office", "vendor", "windows"]
not_affected_if: ["patched-build-installed"]
published_at: "2026-11-10T19:19:47+00:00"
first_seen_at: "2026-11-10T19:24:53+00:00"
updated_at: "2026-11-10T23:06:31+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118716", "first_seen_at": "2026-11-10T19:24:53+00:00"}, {"source": "analyst", "url": "https://app.opencve.io/cve/CVE-2026-118716", "first_seen_at": "2026-11-10T23:06:31+00:00", "cites": ["https://app.opencve.io/cve/CVE-2026-118716", "https://learn.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates"]}]
exploit_sources: []
---

# Microsoft Excel use-after-free allows remote code execution when a user opens a crafted file

Link for people: https://infrastack.ai/live/CVE-2026-118716 (this .md is for agents)

A use-after-free bug in Microsoft Office Excel lets an unauthorized attacker run code over a network. NVD rates it high (CVSS 8.8).

_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 Nov 10 2026 build for your channel fixed 2610 20527.20196
- 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:Microsoft Office for Mac (365, LTSC 2021, LTSC 2024) affected < 16.115.26110837 fixed 16.115.26110837

## How to check

In Excel on Windows open File > Account > About Excel and compare the build with the fixed builds above. On Mac (Excel > About Excel) the CVE record lists versions below 16.115.26110837 as affected. Also check Office Online Server (CVE record: below 16.0.10417.20236).

## Fix

Install the November 10, 2026 Office security update. Fixed builds per Microsoft's release notes: Current Channel 2610 build 20527.20196; Monthly Enterprise Channel 2610 build 20527.20194, 2609 build 20430.20264, 2608 build 20326.20320; Semi-Annual Enterprise Channel 2610 build 20527.20192, 2609 build 20430.20262, 2608 build 20326.20318; Office 2024/2021 Retail 2610 build 20527.20196; Office LTSC 2024 Volume Licensed 2408 build 17932.21140; Office LTSC 2021 Volume Licensed 2108 build 14334.21048.

## Timeline

- 2026-11-10T19:24:53+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-118716
- 2026-11-10T23:06:31+00:00 analyst https://app.opencve.io/cve/CVE-2026-118716 — Microsoft release notes list the CVE under Excel for Nov 10 2026 with fixed builds (fix verified there). MSRC guide page not readable by tools; affected ranges taken from the CVE record via OpenCVE, so not marked verified. CVSS vector has UI:R (file open needed). No exploitation or PoC found.

## Documents

- [describes] OpenCVE: CVE record published by Microsoft (CNA) with affected ranges https://app.opencve.io/cve/CVE-2026-118716
- [fix] Microsoft Office security updates release notes (Nov 10, 2026) https://learn.microsoft.com/en-us/officeupdates/microsoft365-apps-security-updates

## 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_