---
id: "CVE-2016-3298"
kind: "vulnerability"
aliases: ["CVE-2016-3298"]
title: "Microsoft Internet Explorer: Microsoft Internet Explorer Messaging API Information Disclosure Vulnerability"
severity: "medium"
cvss: 6.5
epss: 0.33332
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Microsoft Internet Explorer", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "internet-explorer", "windows"]
not_affected_if: ["no-internet-explorer-installed"]
published_at: "2016-10-14T02:59:13+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-2016-3298", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2016-3298", "first_seen_at": "2026-10-23T19:13:45+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2016-3298", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Microsoft Internet Explorer: Microsoft Internet Explorer Messaging API Information Disclosure Vulnerability

Microsoft Internet Explorer's Internet Messaging API improperly handles objects in memory, letting a web page test whether files exist on the victim's disk. The flaw is listed in CISA's Known Exploited Vulnerabilities catalog, so attackers have used it in real attacks.

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

## Affected

- vendor:Microsoft Internet Explorer affected ? fixed ?

## Fix

Apply the Microsoft updates for the affected Internet Explorer versions per vendor instructions, as CISA requires.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2016-3298
- 2026-10-23T19:13:45+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2016-3298
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2016-3298

## From the sources

An information disclosure vulnerability exists when the Microsoft Internet Messaging API improperly handles objects in memory. An attacker who successfully exploited this vulnerability could allow the attacker to test for the presence of files on disk.

CISA required action: Apply updates per vendor instructions.

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