+44 (0)203 88 020 88

Menu

Search

Cyber Security News & Articles

 

Cyber Security
News & Articles

Trusted Cyber Security Experts
25+ Years Industry Experience
Ethical, Professional & Pragmatic

Windows Zero-Day Flaw Gets Free Unofficial Patch

An actively exploited zero-day flaw that prevents Windows from properly identifying potentially malicious documents by flagging them as downloaded from the web has been given an unofficial patch. The security issue was first brought to Microsoft’s attention by a security researcher 3 month ago, however no official update to correct this has been released. Security patching company 0patch have released a free unofficial patch for this zero-day flaw, which can be used to mitigate the risk of this vulnerability until an official Windows patch becomes available. 

The flaw affects a Windows security feature that is designed to flag documents and executables downloaded from untrusted sources on the web. Windows Mark of the Web (MotW) label is used to trigger the display of warnings about the file’s source to the user, and is used by Windows, Microsoft Office, web browsers, and other apps to warn them to treat the file with caution. It is used by Smart App Control to identify potentially malicious executables and warn users before they proceed with opening untrusted apps, and a Microsoft Office file with a MotW flag also has its macros disable by default. 

Windows MotW should flag all files, including extracted ZIP archive files, using an alternative data stream Zone.Id, which is used to provide extra information about the file without modifying the contents of the file. However, due to the zero-day flaw that is currently unpatched, MotW is not being applied automatically to any files extracted from a ZIP archive. This means that malicious files extracted from a ZIP archive are not blocked by Smart App Control, and do not have their macros disabled. Attackers are known to be actively exploiting this vulnerability to deliver malware via ZIP archived files. 

The unofficial patch works to correct the labelling of these files extracted from ZIP archives so that Windows correctly identifies them with MotW. As a result, security software and mechanisms that rely on searching for the MotW label can correctly warn and protect users about these documents. The micropatch is available for Windows 10 v1803 and later, Windows 7 with or without ESU, Windows Server 2012, 2012 R2, 2016, 2019, and 2022, and Windows Server 2008 R2 with or without ESU. An 0patch account is needed in order to download and apply this free patch, which is the best mitigation of an exploit for this flaw until an official Windows patch is released. 

 

 

Subscribe to our monthly newsletter today

If you’d like to stay up-to-date with the latest cyber security news and articles from our technical team, you can sign up to our monthly newsletter. 

We hate spam as much as you do, so we promise not to bombard you with emails. We’ll send you a single, curated email each month that contains all of our cyber security news and articles for that month.

Why Choose SecureTeam?

Customer Testimonials

“We were very impressed with the service, I will say, the vulnerability found was one our previous organisation had not picked up, which does make you wonder if anything else was missed.”

Aim Ltd Chief Technology Officer (CTO)

"Within a very tight timescale, SecureTeam managed to deliver a highly professional service efficiently. The team helped the process with regular updates and escalation where necessary. Would highly recommend"

IoT Solutions Group Limited Chief Technology Officer (CTO) & Founder

“First class service as ever. We learn something new each year! Thank you to all your team.”

Royal Haskoning DHV Service Delivery Manager

“We’ve worked with SecureTeam for a few years to conduct our testing. The team make it easy to deal with them; they are attentive and explain detailed reports in a jargon-free way that allows the less technical people to understand. I wouldn’t work with anyone else for our cyber security.”

Capital Asset Management Head of Operations

“SecureTeam provided Derbyshire's Education Data Hub with an approachable and professional service to ensure our schools were able to successfully certify for Cyber Essentials. The team provided a smooth end-to-end service and were always on hand to offer advice when necessary.”

Derbyshire County Council Team Manager Education Data Hub

“A very efficient, professional, and friendly delivery of our testing and the results. You delivered exactly what we asked for in the timeframe we needed it, while maintaining quality and integrity. A great job, done well.”

AMX Solutions IT Project Officer

“We were very pleased with the work and report provided. It was easy to translate the provided details into some actionable tasks on our end so that was great. We always appreciate the ongoing support.”

Innovez Ltd Support Officer

Get in touch today

If you’d like to see how SecureTeam can take your cybersecurity posture to the next level, we’d love to hear from you, learn about your requirements and then send you a free quotation for our services.

Our customers love our fast-turnaround, “no-nonsense” quotations – not to mention that we hate high-pressure sales tactics as much as you do.

We know that every organisation is unique, so our detailed scoping process ensures that we provide you with an accurate quotation for our services, which we trust you’ll find highly competitive.

Get in touch with us today and a member of our team will be in touch to provide you with a quotation. 

0

No products in the basket.

No products in the basket.