Beware!! New Ad-Blocking Chrome Extension That Injects Malicious Ads

A new malicious browser extension, known as AllBlock has been detected to be injecting cloaked affiliate links that usually generate commissions for the developers. 

This malicious extension is available for both the Chrome and Opera browsers, and it has been injecting ads, referral affiliate codes inside different search results.

Recognizing the threat

This threat was detected by Imperva during a regular analysis on August 22, 2021. They have claimed that one of the extensions that are hxxps[:]//frgtylik[.]com/KryhsIvSaUnQ[.]js, works in a particular way that we have mentioned below:-

  • At first, the script sends a record of all the links that are present on the page, which also include the full URL of the page, to a remote server.
  • Next, the server passes the list of domains it requires to redirect back to the script.
  • And whenever the user taps on a link that has been modified, the user will then be hijacked to a separate page.

Script deception techniques

However, in this malicious threat attack, the threat actors have a malicious JavaScript file that includes a mechanism with the motive to disturb analysis:-

  • Generally, it clears the debug console every 100ms.

Moreover, it also detects debugging:-

  • As it searches for Firebug initialized variables to detect it.

Not only this even the threat actors also exclude some major search engines and in this list, the first and the important one to get excluded is the Russian engines; while they do so in order to avoid detection.


In this malicious threat, the threat actors have trained them so well that it was hard to detect them. However to avoid detection and to make the extension look legitimate, the threat actors eventually perform ad blocking functionality. 

The threat actors inject a code that connects them back to the extension just by using the standard browser extension communication channel as soon as possible. Soon after that, the threat actors listen for messages that would analyze and will be executed as code.

Influence of Ad Injection & Link to Previous Campaigns

Ad injection has a great impact that can harm any website, as after the ad injection is used, eventually, the performance of the site as well as the user experience starts decreasing, and as time passes it makes the websites slower and users face a lot of difficulties to use the site.

Even there are some other impacts as well like loss of customer trust and loyalty, revenue loss from ad placements, blocked content, and diminished conversion rates.

These kinds of attacks are increasing day by day, despite all the efforts that are being made by security experts and companies.

And for these reasons, they have strongly recommended users use the proper security tools, and mechanisms to remain protected. Doing this will help them to block malicious javascript and other threats.

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