---
id: "CVE-2014-0322"
kind: "vulnerability"
aliases: ["CVE-2014-0322"]
title: "Microsoft Internet Explorer: Microsoft Internet Explorer Use-After-Free Vulnerability"
severity: "critical"
cvss: 9.3
epss: 0.85122
exploited: true
status: "open"
category: "runtime"
products: [{"name": "Microsoft Internet Explorer", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "internet-explorer", "runtime", "windows"]
not_affected_if: ["no-internet-explorer-installed"]
published_at: "2014-02-14T16:55:07+00:00"
first_seen_at: "2026-10-23T19:11:52+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-2014-0322", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2014-0322", "first_seen_at": "2026-10-23T19:13:45+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2014-0322", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Microsoft Internet Explorer: Microsoft Internet Explorer Use-After-Free Vulnerability

Microsoft Internet Explorer has a use-after-free memory bug that lets a remote attacker run code. CISA lists it as exploited in the wild, and the EPSS exploitation probability is 0.851.

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

## Affected

- vendor:Microsoft Internet Explorer affected ? fixed ?

## Fix

Apply updates per vendor instructions; the sources do not name the patched version or KB.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-0322
- 2026-10-23T19:13:45+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2014-0322
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2014-0322

## From the sources

Use-after-free vulnerability in Microsoft Internet Explorer 9 and 10 allows remote attackers to execute arbitrary code via vectors involving crafted JavaScript code, CMarkup, and the onpropertychange attribute of a script element, as exploited in the wild in January and February 2014.

---

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