How to spot a malicious browser extension?

1. Unusual Permissions: If a browser extension requests permission to access information or perform actions that are not relevant to its functionality, this can be a red flag.Ex - A browser extension called "Hover Zoom" requested permission to access user data on all websites, which it did not need to provide its primary function. The extension was found to be collecting user data and sending it to a third-party server.
2. Pop-up Ads: A browser extension that claims to block pop-up ads may actually be causing an increase in the number of pop-up ads and unwanted redirects, or injecting ads into the browsing experience.Ex - A browser extension called “StopAd” claims to block ads and trackers, but it has been found to allow some ads to slip through and even inject its own ads. The extension also collects and shares user data with third-party advertisers, which can compromise privacy.
3. Slow Performance: A browser extension that promises to speed up the browsing experience may actually slow down the browser and cause errors. This could be a sign that he extension is poorly coded or contains malicious code.Ex - A browser extension called “Click&Clean” claims to speed up browsing by clearing browsing history and other data to free up space and improve performance. However, the extension can cause slow performance and crashes, especially when used with other extensions.
4. Unfamiliar or Suspicious Extensions: We come across a browser extension that we don't recognize or that has a suspiciously high number of negative reviews. It's best to avoid installing this extension, as it could be a sign that it is malicious or potentially harmful.Ex - A Chrome extension called "Bookmark Manager" was found to be a phishing scam that stole user data and credentials. The extension had over 10,000 installs before being removed from the Chrome Web Store.
5. Privacy Concerns: A browser extension that offers free VPN services may compromise the privacy if it collects and shares the browsing data with third-party advertisers, potentially using the data for malicious purposes.Ex - A browser extension called "Hola VPN" was found to be collecting and selling user data, including browsing history and personal information, to third-party companies. The extension had over 8 million installs before being removed from the Chrome Web Store.
6. Unwanted Changes: If a browser extension changes the homepage, search engine, or other browser settings without the permission, it could be a sign of a malicious extension.Ex - Delta Search is a browser extension that claims to provide a more customizable search experience. However, it Changes homepage and default search engine without permission, and causes unwanted pop-ups and redirects.
7. High CPU Usage: When it is noticed that the computer's CPU usage is abnormally high, even when not running any programmes or performing any tasks. This could be a sign that a malicious browser extension is running in the background and using up the computer's resources.Ex - A Chrome extension called "Text Mode" was found to be using excessive CPU resources, which caused some users' computers to overheat and crash. The extension had over 100,000 installs before being removed from the Chrome Web Store.

In general, it's important to only install browser extensions from trusted sources and to regularly review and remove any extensions that are no longer in use or that may be malicious.

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