---
id: CVE-2026-77902
title: >-
  Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized
  attacker to execute code over a network.
summary: >-
  Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized
  attacker to execute code over a network.
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-122
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T21:18:21.220'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77902'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77902'
    label: secure@microsoft.com
tags:
  - nvd
ingestedAt: '2026-10-13T19:43:29.056Z'
---

## Overview

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

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.