Windows Defender <= 1.1.26050.11 Elevation of Privilege (RoguePlanet) (CVE-2026-50656)

high Nessus Plugin ID 326451

Synopsis

An antimalware application installed on the remote host is affected by an elevation of privilege vulnerability.

Description

The Malware Protection Engine version of Microsoft Windows Defender installed on the remote Windows host is prior to or equal to 1.1.26050.11. It is, therefore, affected by an elevation of privilege vulnerability:

- Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally. This vulnerability is publicly referred to as RoguePlanet. (CVE-2026-50656)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Enable automatic updates to update the malware engine for the relevant antimalware applications. Refer to Knowledge Base Article 2510781 for information on how to verify that MMPE has been updated.

Plugin Details

Severity: High

ID: 326451

File Name: microsoft_windows_defender_CVE-2026-50656.nasl

Version: 1.1

Type: Local

Agent: windows

Family: Windows

Published: 7/13/2026

Updated: 7/13/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Critical

Score: 9.4

Percentile: 99.81

CVSS v2

Risk Factor: Medium

Base Score: 6

Vector: CVSS2#AV:L/AC:H/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2026-50656

CVSS v3

Risk Factor: High

Base Score: 7

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Vulnerability Information

CPE: cpe:/a:microsoft:windows_defender, cpe:/o:microsoft:windows

Required KB Items: installed_sw/Windows Defender

Patch Publication Date: 7/8/2026

Vulnerability Publication Date: 6/16/2026

Reference Information

CVE: CVE-2026-50656

Detections

Analytics