Browser Hijacker

What Is a Browser Hijacker?

A browser hijacker is a form of potentially unwanted program (PUP) or malware that alters browser settings without the user’s consent. It typically:

Changes your homepage or default search engine
Redirects you to unwanted websites
Injects advertisements into pages
Tracks your browsing activity
Slows down your browser or system performance

Hijackers are often bundled with free software or malicious downloads. One well-known example is OneStart, a productivity app that behaves like a PUP and often leads to browser hijacks.

Symptoms of a Browser Hijacker

Watch for the following red flags:

Your homepage or search engine has changed unexpectedly
You’re redirected to unfamiliar websites (e.g., cast.larianiot.com)
Pop-ups and ads appear even on legitimate websites
Your browser is slower or crashes often
Extensions appear that you didn’t install

How to Identify the Source (Example: OneStartAI)

Check Installed Programs:
- On Windows 10/11, go to Settings > Apps > Installed Apps
- Look for suspicious or unfamiliar names (e.g., "OneStart Software")
Review Browser Extensions:
- Chrome: chrome://extensions
- Edge: edge://extensions
- Firefox: about:addons
- Disable anything you didn’t install yourself.
Check Startup and Scheduled Tasks:
- Use Task Manager > Startup tab or run msconfig
- Open Task Scheduler and look for suspicious triggers or app launchers
Inspect Shortcut Targets:
- Right-click your browser shortcut > Properties
- Look for any appended URLs in the Target field (e.g., ...chrome.exe" http://cast.larianiot.com)

Step-by-Step: How to Fully Remove a Browser Hijacker

1. Uninstall Suspicious Programs

Open Control Panel > Programs and Features or Settings > Apps
Locate and uninstall:
OneStart
Any other recently installed or unknown applications

2. Reset Browser Settings

Chrome: Settings > Reset and clean up > Restore settings to their original defaults

Edge: Settings > Reset settings > Restore settings to their default values

Firefox: Help > More Troubleshooting Information > Refresh Firefox

3. Run Anti-Malware Tools

Use trusted tools to scan and remove residual components:

Scan your system thoroughly, and quarantine or remove all detected threats.

4. Clean Browser Data

Clear cache, cookies, and site settings:
chrome://settings/clearBrowserData (for Chrome)
This helps eliminate hijacker persistence via stored data.

5. Delete Temporary Files

Use Disk Cleanup:
Start > type “Disk Cleanup” > Select drive > Clean temporary files

6. Examine the Hosts File

Located at C:\Windows\System32\drivers\etc\hosts
Open with Notepad and make sure there are no unfamiliar redirects (e.g., 127.0.0.1 example.com)

Prevention Tips

Avoid freeware bundles from unofficial sources
Always use “Custom” install to uncheck optional offers
Keep your OS and browser updated
Use a reputable antivirus and real-time protection
Regularly audit extensions and installed apps