Potentially unwanted application (PUA)

What are potentially unwanted applications (PUAs)?

These are hidden applications, unknowingly downloaded alongside legitimate apps, which clutter your PC with ads, hijack your browsers, slow down your PC – and frequently collect data on what you click on.

How they spread

PUAs often get onto user’s PCs via social engineering tactics; legitimate applications trick the user to install additional software.

This tend to be done via:

  • Writing up a misleading description of the software
  • Claiming that the installation of additional software is mandatory
  • Installing additional software by default
  • Tricking the user into taking unnecessary actions

What they are after

PUAs can be extremely irritating. Among other things, they can collect information about your surfing habits and then transmit it to third parties without notification or consent. They can also hijack browsers to change default settings (search engine and start page).

Known cases

Some of the most commonly encountered PUAs include OpenCandy, InstallCore, and Media Get.

How to block PUAs

To protect yourself from PUAs, consider the following guidelines:

  • When downloading any software/app, be on the lookout for any pre-checked option boxes.
  • When it comes to terms and conditions, always read at least the title above the fine print to ensure that the terms are for the specific program(s) you want to download.
  • Read through the information in the top navigation bar of an installation wizard to catch names of unwanted programs.
  • Avira Free Antivirus blocks PUAs – even if you didn’t read the terms and conditions!
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