---
id: "CVE-2020-0878"
kind: "vulnerability"
aliases: ["CVE-2020-0878"]
title: "Microsoft Edge and Internet Explorer: Microsoft Edge and Internet Explorer Memory Corruption Vulnerability"
severity: "high"
cvss: 7.5
epss: 0.02696
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Microsoft Edge and Internet Explorer", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "internet-explorer", "microsoft-edge", "ransomware", "vendor", "windows"]
not_affected_if: ["unknown"]
published_at: "2020-09-11T17:15:14+00:00"
first_seen_at: "2026-10-23T19:11:53+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-0878", "first_seen_at": "2026-10-23T19:11:53+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2020-0878", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-0878", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Microsoft Edge and Internet Explorer: Microsoft Edge and Internet Explorer Memory Corruption Vulnerability

Microsoft Edge and Internet Explorer have a memory corruption bug that lets an attacker run code as the current user. CISA lists it as actively exploited and tags it as used in ransomware campaigns.

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

## Affected

- vendor:Microsoft Edge and Internet Explorer affected ? fixed ?

## How to check

Check which browser build is installed: Edge version under edge://settings/help and Internet Explorer via Help > About Internet Explorer. unknown for the affected version range.

## Fix

Apply the Microsoft security update for Edge and Internet Explorer per vendor instructions (CISA required action). Specific fixed build: unknown.

## Timeline

- 2026-10-23T19:11:53+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2020-0878
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2020-0878
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2020-0878

## From the sources

<p>A remote code execution vulnerability exists in the way that Microsoft browsers access objects in memory. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.</p>
<p>An attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft browsers, and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerability. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action, typically via an enticement in email or instant message, or by getting them to open an email attachment.</p>
<p>The security update addresses the vulnerability by modifying how Microsoft browsers handle objects in memory.</p>

---

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