Short bio

PUP.Optional.DefaultSearch is Malwarebytes’ detection name for a family of browser hijackers targeting Chrome, Firefox and Internet Explorer.


The browsers’ default search engine was changed  to one that belonged to the threat-actors.


Malwarebytes blocks the domains that PUP.Optional.DefaultSearch hijacks to using the web protection module.

block 1-1ads.com

Malwarebytes blocks 1-1ads.com


Malwarebytes can detect and remove PUP.Optional.DefaultSearch without further user interaction.

  1. Please download Malwarebytes to your desktop.
  2. Double-click mb3-setup-consumer-{version}.exe and follow the prompts to install the program.
  3. Then click Finish.
  4. Once the program has fully updated, select Scan Now on the Dashboard. Or select the Threat Scan from the Scan menu.
  5. If another update of the definitions is available, it will be implemented before the rest of the scanning procedure.
  6. When the scan is complete, make sure that all Threats are selected, and click Remove Selected.
  7. Restart your computer when prompted to do so.

Add an exclusion

Should users wish to keep this program and exclude it from being detected in future scans, they can add the program to the exclusions list. Here’s how to do it.

The Exclusions tab includes a list of items to be excluded from scans. The items may include files, folders, websites, or applications that connect to the Internet, as well as previously detected exploits.

To access the exclusions in Malwarebytes:

  • Click on the Settings tab in the left pane.
  • Click on the Exclusions tab.
  • Click the Add Exclusion button.
  • Select the exclusion type Exclude a File or Folder and use the Browse button to select the main folder for the software that you wish to keep.


Associated files: 

Chrome extension: iomphmdalfmaifjccmagmllnicjoghhk

Firefox extension: defsearchp@gmail.com.xpi




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