Browser extensions1 are an essential thing for modern web browsing. We may take no notice about them while using your Chrome or Mozilla, however, it’s hard to imagine modern web browsing without advertisements blocking, cookies controlling, privacy management, et cetera. Other plugins have the straight influence on browser interface, adding new wallpapers, interactive widgets or toolkits in the drop-down list. But sometimes the developers of extensions are adding different potentially malicious elements to their products, that allow them to earn money. In this article you will see the detailed explanation of possible danger carried by browser extensions and the importance of proper choosing of the extensions.
First, let’s look at the most popular kind of malicious extensions. In 2020, there is a massive amount of extensions in Chrome Web Store, that are distributed as “docx to pdf file converter” or “special extensions for searching live sport streams”. However, you will see unwanted advertisements instead of offered functions. As a variant, your search engine will be changed to one that has a partnership with extension creator (i.e. Yandex, Yahoo, Bing or so). They are not harmful by themself, and may be easily deleted if you install it manually. But it’s important to note that they usually appear after the malware injection, and last will block any attempt to remove it.
The second type of malicious add-ons for your browser is activity trackers. They may be hidden under the guise of advertisement blocker, or exactly as the online activity tracker/firewall for your children. Some of these extensions really have the announced functions, but besides them add-ons will collect some information about you. Phone numbers, search queries, email addresses – that are the typical targets for the developers of these extensions. Later, this information will be sold to advertisers, who can send you different spam to email, or even offer their products by phone.
The most dangerous is the last type – phishing browser extensions. Such add-ons are distributed exclusively as a part of malware bundles, and used to display the fake variants of well-known websites (Twitter, Facebook, Gmail, LinkedIn, and so on). On these fakes you are offered to enter your login and password, but after this action your credentials will be stolen. In the specific (and the most sly) cases, some legit add-ons may be used in this scheme – the developers’ accounts may be stolen, or the developers may be bribed to allow their applications to be used for malicious targets. After being stolen, your account may be used for spamming with malicious attachments, or as a part of botnet to perform DDoS-attacks or getting a profit from pay-per-view ads.
How can I avoid browser extensions traps?
First, you need to pay attention to what you are installing. If the add-on you are going to use needs to control your search engine, or to get access to some of your personal data, it is better to avoid installing such a plugin. Nowadays, with the new GDPR Compliance law, all browsers would need to prompt users for permission on the extension activities. So, the only thing you need to check precisely is the pop-up window which appears in the process of plugin installation.
But paying attention to installation notes will not save you from phishing. To be sure that you are going to log into real Facebook or LinkedIn, check the left side of the address bar. Besides the website address, you can also see there a grey lock image, showing you that this website has an approved https certificate. Fake pages are not able to get this certificate, so you will see “Not secure” signs on such sites. If you have seen such a page once, scan your PC with an antimalware program as soon as possible.
And the final advice is using antivirus software to avoid any malware, including adware and unwanted programs, like described browser extensions. Making use of anti-malware programs must be something like washing hands for every user – essential and regular. Such an easy operation will make your daily computer actions free of any worries and risks. Of course, you are free to make a decision by yourself, and use an embedded Microsoft antivirus solution, or don’t use anti-malware software at all. But keep in mind that using the computer without antivirus software is a suitable option only for experienced users, who are able to distinguish legit and safe programs from risky and malicious.
- More about browser extensions on Wikipedia