How malware protection works


Every day tens of thousands of people fall victims to virus attacks or fraud on the Internet. To protect Adguard users from such threats, we have added special filters to the program, that protect you from malicious and phishing websites.

At the moment we have categorized more than 15 million sites, and our filters contain about 1.5 million phishing and malware sites. Just think about it: 10% of all known sites can be dangerous for you! Inexperienced user can easily become a victim of fraudsters or hackers. We hope that the use of protection against malicious websites will help you avoid all hazards that you may encounter.

How does a check work?

Method and quality of a check depends on what product you use. If you are using one of our browser extensions, then Adguard inspects only those pages that you visit. If you are using Adguard for Windows, then in addition to the page itself, we check each object loaded on it, giving you the best protection.

Adguard for Windows

We use the protocol Safe Browsing API version 2.2 for the work with our filters. Use of this protocol allows us to keep your personal data absolutely safe. Our server knows nothing about the websites, that you visit. We use hash prefixes for checks, not the opened URLs.

Approximate algorithm of the Browsing Security module functioning is shown in the picture below.

Functioning algorithm of Browsing Security module in Adguard for Windows.

Other Adguard versions

Browser extensions (as well as Adguard for Android and Adguard for Mac) work differently, using the so called Lookup API to do the check of pages that you visit. Every time you visit any website, local client exchanges information with our backend server in a form of hashes and hash prefixes. For those who are interested in the process on a deeper level, the link above will be helpful. As a result of that exchange, local client determines if the website is from blacklist or not.

It is very important to notice that we never get any information that could allow us to determine which website you visit and use that data in any way.

Approximate algorithm of the Browsing Security module functioning is shown in the picture below.

Functioning algorithm of Browsing Security module in Adguard browser extensions.

Adguard filters

Currently we support the work of two Adguard filters. One of them is aimed at protecting you against phishing and fraudulent websites. Another at protection against malicious websites, visiting of which can lead to virus infection.

Phishing sites filter

Phishing — is a type of online fraud aimed at gaining access to confidential data of users - username and password. If you are interested in this topic, we suggest that you read this article at Wikipedia.

Apart from phishing sites, this filter also contains different fraudulent sites. All kinds of "scam", selling of nonexistent content, and such.

Malicious sites filter

This filter contains links to pages that lead to the execution of malicious code. It can initiate leakage or loss of data or harm the device of a user. It can be authorized (for example, when downloading and running the executable file) or unauthorized (for example, when being attacked with spyware).

How do we fill up our filters?

Our filters are constantly filled up with new addresses. Since most of the work is automated, you can be sure that new malware and phishing addresses fall into our database as quickly as possible.

Adguard Browsing Security Community

An important tool for maintaining the highest level of filtering is a mechanism: Adguard Browsing Security Community. Any user of our products - be it Adguard for Windows or browser extension - can become a member of the community and help us in making of Adguard filters.

In the picture below we described an algorithm of Browsing Security Community work:

The way Adguard Browsing Security Community works

Want to help?

We will gladly accept any help! If you want to send us a complaint to a phishing or malware site, you can do it via technical support, or on our Forum.

False-positive responses

Occasionally some websites that are not dangerous fall into Adguard filters. We tried to reduce the percentage of false-positives, but, nevertheless, they can occur. If you come across this behavior of Adguard, please send us a complaint against the false-positive alarm. You can submit such complaints via our technical support or on our Forum.

Operating System:
Adguard for Android provides you with a reliable and manageable protection. Adguard removes all the annoying ads from web pages and applications, blocks loading of dangerous websites, and will not allow anyone to track your activities on the Internet. Adguard stands out against its analogues as it can work both in HTTP proxy and VPN mode.
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Operating Systems Android 4.0.3 +
RAM from 700mb
Free Disk Space 30mb
Adguard for Mac is the first adblocker developed specifically for OS X. Not only it blocks ads and annoying popups in any browser, but also protects you from online trackers and dangerous websites. Adguard offers you simple and intuitive interface with such additional features like Adguard Assistant and filtering log.
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Operating Systems OS X 10.7 (64 bit) +
RAM from 2Gb
Web Browsers Safari, Google Chrome, Opera, Yandex browser, Mozilla Firefox and other
Free Disk Space 60mb
Adguard for Windows provides you with a reliable and manageable protection that immediately and without your participation filters loading web pages. Adguard removes all the annoying ads and popups, blocks dangerous websites, and does not allow anyone to track your activities on the Internet.
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Operating Systems Windows XP SP3, Vista, 7, 8, 8.1, 10
RAM from 512mb
Web Browsers Microsoft Edge, Internet Explorer, Google Chrome, Opera, Yandex Browser, Mozilla Firefox and other
Free Disk Space 50mb
Adguard for iOS is an app that protects you from annoying ads in Safari. Moreover, it prohibits online tracking and secure privacy of your personal data. After downloading the app, you get the ad-free and safe Internet, where websites open much faster. Try now and enjoy web surfing experience on your iPhones and iPads.
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Compatibility Requires iOS 9.0 or later. Compatible with iPhone 5s, iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPad Air, iPad Air Wi-Fi + Cellular, iPad mini 2, iPad mini 2 Wi-Fi + Cellular, iPad Air 2, iPad Air 2 Wi-Fi + Cellular, iPad mini 3, iPad mini 3 Wi-Fi + Cellular, iPad mini 4, iPad mini 4 Wi-Fi + Cellular, iPad Pro, iPad Pro Wi-Fi + Cellular, and iPod touch (6th generation).
Web Browsers Safari
Free Disk Space 24.4 MB