CVE-2018-8639 - PatchNow

📋 Vulnerability Details

Data Source: CIRCL

Confidence: HIGH

Exploitation Method: OTHER

CVE Published: 2018-12-12

Added to CISA KEV: 2025-03-03 2273 DAYS BETWEEN CVE AND KEV

🎯 Recommendations:

CRITICAL: Check for indicators of compromise - this vulnerability is in CISA KEV indicating active exploitation in the wild. Review logs for privilege escalation activities, check for unauthorized access, verify system integrity
Apply Microsoft security patches immediately for all affected Windows systems
Monitor for unusual privilege escalation activities and unauthorized administrative access
High patch priority - actively exploited vulnerability affecting core Windows component

🔍 Web Intelligence (Kagi · 2026-06-04)

CVE-2018-8639 is a critical elevation of privilege vulnerability in the Microsoft Windows `Win32k` component, specifically involving the improper handling of objects in memory ^[2].

Technical Details and Exploitation

Attack Method: The vulnerability is a local privilege escalation (LPE) flaw ^[1]. It requires an attacker to already have local access to the system and be authenticated ^[1].
Impact: Successful exploitation allows an attacker to execute arbitrary code in kernel mode, potentially leading to a complete system compromise ^[1].
Exploitation in the Wild: While some sources have indicated that the vulnerability has been associated with known ransomware exploitation ^[1], it is primarily categorized as an LPE vulnerability that requires prior local access.

Affected Products and Mitigation

The vulnerability affected a wide range of Microsoft Windows versions, including:

Windows 7
Windows 8.1
Windows 10
Windows Server 2008, 2008 R2, 2012, 2012 R2, 2016, and 2019
Windows RT 8.1 ^[2]

Status: This vulnerability was addressed by Microsoft in the December 2018 security updates ^[3]. Users and administrators are advised to ensure that all applicable security patches provided by Microsoft have been applied to mitigate this and other related vulnerabilities.

Sources