---
id: "CVE-2018-0798"
kind: "vulnerability"
aliases: ["CVE-2018-0798"]
title: "Microsoft Office: Microsoft Office Memory Corruption Vulnerability"
severity: "critical"
cvss: 9.3
epss: 0.95121
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Microsoft Office", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "microsoft-office", "windows"]
not_affected_if: ["unknown"]
published_at: "2018-01-10T01:29:00+00:00"
first_seen_at: "2026-10-23T19:11:53+00:00"
updated_at: "2026-10-23T21:57:34+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2018-0798", "first_seen_at": "2026-10-23T19:11:53+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2018-0798", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-0798", "first_seen_at": "2026-10-23T21:57:34+00:00"}]
---

# Microsoft Office: Microsoft Office Memory Corruption Vulnerability

Microsoft Office has a memory corruption flaw in how it handles objects in memory. An attacker who gets a crafted file opened can run code as the current user, and it is known to be exploited in the wild and chained with CVE-2018-0802.

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

## Affected

- vendor:Microsoft Office affected ? fixed ?

## Fix

Apply the Microsoft Office security updates per vendor instructions (CISA required action); the specific patched build is unknown from the sources.

## Timeline

- 2026-10-23T19:11:53+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2018-0798
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2018-0798
- 2026-10-23T21:57:34+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2018-0798

## From the sources

Microsoft Office contains a memory corruption vulnerability due to the way objects are handled in memory. Successful exploitation allows for remote code execution in the context of the current user. This vulnerability is known to be chained with CVE-2018-0802.

CISA required action: Apply updates per vendor instructions.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_