Windows update flaw could be a hidden gateway to zombie vulnerabilities

Technology August 30, 2024

Hackers downgrade your Windows version to take control of your PC

windo

Researchers have discovered a new way hackers could use to exploit Windows devices. They have found a vulnerability in your PC’s operating system that could let threat actors downgrade it to an older version of Windows.

So, if you’re on Windows 11, they could roll it back to Windows 10, which would expose a bunch of old vulnerabilities they could use to take full control of your system.

Microsoft told CyberGuy it is working on a fix and claims the vulnerability is still just theoretical — the company hasn’t seen anyone try to exploit it yet. I’ll go over the details of this security flaw and share some tips to help you protect your PC.

GET SECURITY ALERTS, EXPERT TIPS — SIGN UP FOR KURT’S NEWSLETTER — THE CYBERGUY REPORT HERE

A person working on a Windows PC. (Kurt "CyberGuy" Knutsson)

How hackers exploit Windows downgrades

Alon Leviev, a researcher at SafeBreach, spotted the security flaw. Leviev says he started digging into downgrade attack methods after noticing that a big hacking campaign last year used malware called the "BlackLotus UEFI bootkit" that worked by downgrading the Windows boot manager to an old, vulnerable version.

Leviev found a way to downgrade Windows — either the whole operating system or just certain parts of it. He then created a proof-of-concept attack using this method to turn off a Windows protection called Virtualization-Based Security (VBS) and target the highly privileged code running in the computer’s core, known as the "kernel."

WHAT IS ARTIFICIAL INTELLIGENCE (AI)?

Normally, when your PC requests an update, it communicates with a secure Microsoft server that controls the update process. Leviev couldn’t directly alter the server-controlled files, but he found that one key — "PoqexecCmdline" — was not locked, allowing him to manipulate the update process.

Using this control, Leviev was able to downgrade critical Windows components — including drivers, dynamic link libraries and the NT kernel — to older versions with known vulnerabilities. He also found ways to downgrade important security features like the Windows Secure Kernel, Credential Guard, the hypervisor and Virtualization-Based Security (VBS).

To make it clearer, older versions of Windows have unpatched issues that hackers can exploit to steal your data or take control of your PC. These issues get fixed when you update to the latest software version. But if hackers manage to downgrade your PC to an old, vulnerable version, they can easily break into your system.

Windows software running on these laptops. (Kurt "CyberGuy" Knutsson)

BEST POWER STRIPS AND SURGE PROTECTORS 2024

What is Microsoft doing about the issue?

Microsoft has acknowledged the security flaw and is actively working on a fix. In response to an inquiry from CyberGuy, a company spokesperson provided the following statement:

"We appreciate the work of SafeBreach in identifying and responsibly reporting this vulnerability through a coordinated vulnerability disclosure. We are actively developing mitigations to protect against these risks while following an extensive process involving a thorough investigation, update development across all affected versions, and compatibility testing, to ensure maximized customer protection with minimized operational disruption."

The Redmond, Washington-based company said it is developing a security update that will revoke outdated, unpatched VBS system files to mitigate this threat. Due to the complexity of blocking such a large quantity of files, rigorous testing is required to avoid integration failures or regressions. The company added:

"We are not aware of any attempts to exploit the technique outlined in this report and are continuing to monitor the threat landscape as it evolves."

HP laptop running Windows. (Kurt "CyberGuy" Knutsson)

WINDOWS FLAW LETS HACKERS SNEAK INTO YOUR PC OVER WI-FI

Learn how to update your Windows software

Microsoft says that hackers haven't exploited the vulnerability yet, and even if they do, there’s little you can do from your side. Still, as general cybersecurity hygiene, keep your operating system and other software up-to-date.

It is one of the most effective ways to safeguard your devices from known vulnerabilities and security flaws. To update your Windows software and benefit from the latest security patches, follow these simple steps:

For Windows 10 and Windows 11

Click on the Start menu and select "Settings" (or press the Windows key + I shortcut).
In the Settings window, click on "Update & Security."
Under the "Windows Update" section, click "Check for updates."
If updates are available, including the patch for the Wi-Fi driver vulnerability, Windows will download and install them automatically.
Once the installation is complete, you may be prompted to restart your computer to apply the updates.

For Windows 8.1 and Earlier Versions

Open the Control Panel and navigate to "System and Security."
Under the "Windows Update" section, click "Check for updates."
If updates are available, including the patch for the Wi-Fi driver vulnerability, select them and click "Install updates."
Follow the on-screen instructions to complete the installation process.
Restart your computer if prompted to apply the updates.

HOW TO REMOVE YOUR PRIVATE DATA FROM THE INTERNET

Four additional ways to protect your Windows PC

The report says that even if the downgrade flaw is quite undetectable, hackers still need a way to get remote access to your computer. This is where you can stop them. Here are some steps you can take:

1. Install a strong antivirus program: Hackers often gain access to devices by sending infected emails or documents or tricking users into clicking a link that downloads malware. You can avoid this by installing strong antivirus software that will detect any potential threat before it can take over your device or router. Get my picks for the best 2024 antivirus protection winners for your Windows, Mac, Android and iOS devices.

2. Recognize urgent requests as potential scams: Always be wary if someone is urgently requesting you to do something like send money, provide personal information or click on a link — chances are it’s a scam.

3. Use strong and unique passwords: Create strong passwords for your accounts and devices, and avoid using the same password for multiple online accounts. Consider using a password manager to securely store and generate complex passwords. It will help you to create unique and difficult-to-crack passwords that a hacker could never guess. Second, it also keeps track of all your passwords in one place and fills passwords in for you when you’re logging into an account so that you never have to remember them yourself. The fewer passwords you remember, the less likely you will be to reuse them for your accounts. Get more details about my best expert-reviewed Password Managers of 2024 here.

4. Enable two-factor authentication: Enable two-factor authentication whenever possible. This adds an extra layer of security by requiring a second form of verification, such as a code sent to your phone, in addition to your password.

HOW TO REMOVE YOUR PRIVATE DATA FROM THE INTERNET

Kurt’s key takeaways

This latest Windows vulnerability is a major concern, exposing your PC to potential risks by allowing hackers to downgrade your system to an older, less secure version. By exploiting this flaw, attackers could access outdated vulnerabilities and take full control of your machine. While Microsoft is aware of the issue and is working on a fix, the fact that this vulnerability even exists is a stark reminder of how critical it is to stay on top of system updates and security measures. Keep an eye on your system's security and be cautious as more details emerge.

Do you regularly check for and install updates to avoid security threats like this? Let us know by writing us at Cyberguy.com/Contact

For more of my tech tips and security alerts, subscribe to my free CyberGuy Report Newsletter by heading to Cyberguy.com/Newsletter

Ask Kurt a question or let us know what stories you'd like us to cover .

Follow Kurt on his social channels:

Answers to the most-asked CyberGuy questions:

New from Kurt:

Kurt "CyberGuy" Knutsson is an award-winning tech journalist who has a deep love of technology, gear and gadgets that make life better with his contributions for Fox News & FOX Business beginning mornings on "FOX & Friends." Got a tech question? Get Kurt’s free CyberGuy Newsletter, share your voice, a story idea or comment at CyberGuy.com.

Authored by Kurt Knutsson, Cyberguy Report via FoxNews August 30th 2024