Browlock is a portmanteau of browser and lock. The term is used to describe the state of an Internet browser when the user is unable to perform certain actions. A browlock can:
The term is also used in cases where malware opens a browser window for the above purposes without the user actively participating. The browser controls can be hidden so the user would not recognize it as such.
The objectives for this behavior can be numerous, but it in essence the threat actor wants the user to do something he normally wouldn’t have done, such as call a tech support scam number, pay a ransom, or install an extension. You can find more information about browser lockers in our blog post, Regaining Control Over Edge.