Watch out for phony PDF reader apps.

Even mainstay free Adobe Reader can be compromised by cybercriminals and posted to sketchy software download sites visited by the unwary.

Myriad off-brand free PDF reader apps are often malicious schemes to infect computers and steal unwary users’ data.

If you fall for a malicious PDF reader app and/or PDF file, results can be dire. Hackers can install spyware, web hijackers can take remote control of your computer. Your identity can be stolen. Your data and that of your organization can be totally destroyed by ransomware.

Any wonder why free PDF apps are so popular with cybercriminals?

Infected PDF apps are easy for cybercriminals to create and distribute. These apps can be programmed to send copies of every PDF you create, view and edit to cybercriminals.

Malicious code can be embedded within PDF files and mass distributed or targeted to individuals via phishing emails or infected web links. A single click on an infected PDF can infect untold numbers of computer.

So, why would anyone install a phony PDF reader from sketchy sites when there are legitimate, free, safe and high quality apps readily available or already built-in?

Apple’s Preview app comes pre-installed on every Mac. Windows 10 PCs can read PDF files in Microsoft's Edge web browser. Microsoft Office can open and edit PDFs created in Word and sibling Office apps. Macs and PCs can read PDFs in Google’s Chrome browser (adjust Chrome’s Settings). Proven, genuine, free and safe versions of Adobe Reader for Macs and PCs are also available from

My personal fav PDF and image reader is Apple’s excellent Preview app. Preview obviates the need for any other PDF reader app. Preview reads .jpg, .png, .tiff, and even Photoshop .psd files, and it has a limited but very handy set of image editing and file conversion tools. I use Preview every day.

Exceptions? When digitally signing secure PDF documents like contracts or filling out legitimate data capture forms, genuine Adobe Reader may be required. Download and install the real deal only from

Of course, there is a role for Adobe Acrobat Professional in education, law, business, high tech, publishing, graphic arts, media, heavy industry and more.

But, for most of us, a genuine, free and safe PDF app should be our tool of choice.

© Quentin Leo