---
id: "CVE-2015-2546"
kind: "vulnerability"
aliases: ["CVE-2015-2546"]
title: "Microsoft Win32k: Microsoft Win32k Memory Corruption Vulnerability"
severity: "high"
cvss: 8.2
epss: 0.10107
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Microsoft Win32k", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "ransomware", "windows", "windows-server"]
not_affected_if: ["patched-hosts"]
published_at: "2015-09-09T00:59:53+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-2015-2546", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2015-2546", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2015-2546", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Microsoft Win32k: Microsoft Win32k Memory Corruption Vulnerability

A memory corruption flaw in the Win32k kernel-mode driver of Windows and Windows Server lets a local user run a crafted application to gain higher privileges. CISA lists it as known exploited, and the tags say it has been used in ransomware campaigns.

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

## Affected

- vendor:Microsoft Win32k affected ? fixed ?

## How to check

Run winver or systeminfo on each Windows host and compare the build against Microsoft's security bulletin MS15-051 for this CVE.

## Fix

Apply the Microsoft update for MS15-051 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-2015-2546
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2015-2546
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2015-2546

## From the sources

The kernel-mode driver in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT Gold and 8.1, and Windows 10 allows local users to gain privileges via a crafted application, aka "Win32k Memory Corruption Elevation of Privilege Vulnerability," a different vulnerability than CVE-2015-2511, CVE-2015-2517, and CVE-2015-2518.

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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_