MatrixPDF Puts Gmail Users at Risk with Malicious PDF Attachments

[Khushal]

Content source

https://www.varonis.com/blog/matrixpdf

MatrixPDF Puts Gmail Users at Risk with Malicious PDF Attachments

Discover how PDF-based malware attacks work and how AI-powered email security can detect and block threats before they reach your inbox.

www.varonis.com

 

[Parkinsond]

MatrixPDF Puts Gmail Users at Risk with Malicious PDF Attachments

Discover how PDF-based malware attacks work and how AI-powered email security can detect and block threats before they reach your inbox.

www.varonis.com

It bundles phishing and malware features into a builder that alters legitimate PDF files with fake secure document prompts, embedded JavaScript actions, content blurring, and redirects.

Always disable creation of links of urls and execution of javascript in any pdf reader.

 

[Divine_Barakah]

Always disable creation of links of urls and execution of javascript in any pdf reader.

That's why I never use the in-built pdf functionality in browsers.

 

[Parkinsond]

That's why I never use the in-built pdf functionality in browsers.

Edge, after the latest update, developed an interesting bug; after adding text to a pdf file (saved on disk) using its annotation, its size duplicates almsot 100 times.

Reported by several users on Reddit.

 

[Sampei.Nihira]

That's why I never use the in-built pdf functionality in browsers.

Hi,
Do you use third-party PDF software to open PDFs online?

I use third-party software (SumatraPDF) only to open offline PDFs saved on my PC, and this third-party software is also on the MD Exploit list, and of course I block connections via firewall.

 

[Divine_Barakah]

Hi,
Do you use third-party PDF software to open PDFs online?

I use third-party software (SumatraPDF) only to open offline PDFs saved on my PC, and this third-party software is also on the MD Exploit list, and of course I block connections via firewall.

I don't open PDF files online. I download them and use either Swifdoo or Wondershare.

 

[lokamoka820]

I think SumatraPDF will always remain the most secure PDF reader, simply because it has no JavaScript at all.

 

[Parkinsond]

I think SumatraPDF will always remain the most secure PDF reader, simply because it has no JavaScript at all.

WPS Office pdf editor and OnlyOffice pdf editor have no JS also.

 

[Sampei.Nihira]

I don't open PDF files online. I download them and use either Swifdoo or Wondershare.

I don't understand how you can know before downloading it to your PC whether the PDF is useful and interesting to you.
However, once the PDF is on your PC, you use your browser to manipulate it, so it seems to me that it's the same thing.

 

[Sampei.Nihira]

However, guys, for security reasons, it is better to use your browser to open PDFs online rather than third-party software, and not just because of the Integrity Level.
The browser's IL is set to untrusted, while third-party software has a medium IL at best.

Theoretically, it would be possible to lower the IL of third-party software.
I did this a long time ago using Icacls, but then I asked myself why I was going to all this trouble...

Good evening, everyone.

 

[Divine_Barakah]

I don't understand how you can know before downloading it to your PC whether the PDF is useful and interesting to you.
However, once the PDF is on your PC, you use your browser to manipulate it, so it seems to me that it's the same thing.

I simply download the pdf and scan it. Then I open it using Swifdoo PDF or Wondershare PDFelement. I don't use the browser to edit pdf files.