Saturday, October 17, 2026

Newly Patched Windows Zero-day Lets Hackers Take Complete Control of the Windows System

Very recently patched Windows zero-day vulnerability (CVE-2019-0859) in win32k.sys let hackers take control of unpatched Windows systems.

Security researchers from Kaspersky team recent addressed this Zero-day vulnerability in win32k.sys while it made an attempt to exploit one of their customers Microsoft Windows operating system.

A Local Privilege Escalation vulnerability was then reported later to Microsoft and released a patch for Zero-day along with 74 other security vulnerabilities.

This is actually the fifth vulnerability that consecutive exploited Local Privilege Escalation vulnerability in Windows that uncovered by Kaspersky team researchers, here the previous zero-days in very recent past.

Zero-day Exploit Process in Windows win32k.sys

This Vulnerability is presented in the CreateWindowEx, a function that
creates an overlapped, pop-up, or child window with an extended style.

Attackers Exploiting this elevation of privilege vulnerability in Windows when Win32k component fails to properly handle objects in memory.

A PowerShell script mainly used by attackers for the post-exploitation process with a Base64 encoded command. 

The ultimate goal of this PowerShell script to download a second-stage script from https//pastebin.com.

This Second stage of the PowerShell executes the final stage which is also a PowerShell Script that you can see in below image.

Windows Zero-day
Third stage PowerShell script

According to Kaspersky, the third script is very simple and does the following:

  • Unpacks shellcode
  • Allocates executable memory
  • Copies shellcode to the allocated memory
  • Calls CreateThread to execute shellcode

At the final stage, the shellcode is to make a trivial HTTP reverse shell that leads to attackers gain complete control of the targeted victims Windows system.

You can follow us on Linkedin, Twitter, Facebook for daily Cybersecurity updates also you can take the Best Cybersecurity courses online to keep your self-updated.

Also Read:

Microsoft Hacked – Hackers Compromised The Microsoft Employee’s Account to Gain Access the Customers Email

Unpatched Internet Explorer Zero-day Vulnerability Lets Attackers Hack Windows PC & Steal Files

Balaji
Balaji
BALAJI is an Ex-Security Researcher (Threat Research Labs) at Comodo Cybersecurity. Editor-in-Chief & Co-Founder - Cyber Security News & GBHackers On Security.

Hot this week

How To Access Dark Web Anonymously and know its Secretive and Mysterious Activities

What is Deep Web The deep web, invisible web, or...

How to Build and Run a Security Operations Center (SOC Guide) – 2023

Today’s Cyber security operations center (CSOC) should have everything...

Russian Hackers Bypass EDR to Deliver a Weaponized TeamViewer Component

TeamViewer's popularity and remote access capabilities make it an...

Web Server Penetration Testing Checklist – 2026

Web server pentesting is performed under three significant categories: identity,...

ATM Penetration Testing – Advanced Testing Methods to Find The Vulnerabilities

ATM Penetration testing, Hackers have found different approaches to...

AI-Assisted Hackers Compromise Government Linux Servers to Deploy Backdoors and Steal Credentials

Hackers used AI-assisted scripts to compromise government Linux servers,...

Researchers Demonstrate iOS 27.0.1 Untethered Jailbreak on iPhone 18 Pro

Security researchers from Calif (Calif.io) demonstrated a working untethered...

Google Android Flags 5 Million Suspected Scam Calls and Texts Monthly

Google says its Android scam-detection capabilities now flag more...

Researchers Uncover 20,000 Malicious Cloudflare Pages Domains Used in Tech Support Scams

More than 20,000 malicious Cloudflare Pages subdomains used by...

Related Articles

Recent News