1424626 - Firefox window hijacked by malicious site - difficult to close window

Status: RESOLVED DUPLICATE of bug 1412559

(Firefox :: Untriaged, defect)

Description

[Jukka Alasalmi]

Attachment: Source code of the malicious website

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171129230719

Steps to reproduce:

Browsed the web, when a malicious popup hijacked the Firefox window (working on Linux, Firefox 57.0.1 / 64-bit).


Actual results:

It is very difficult to close the window: as soon as the mouse leaves the content area of the window, Firefox opens a modal dialog, roughly translated in English as: "The page can be displayed only by resending data Firefox already sent. Resending the data will repeat the earlier executed action (such as search or order from an online store)." Clicking on Cancel or Resend will only close the dialog until mouse is moved out of the content area again. As the dialog is modal, the window cannot be closed.

The site address is http://upcheckext.com/ff/?_subid=gu7u2346c04kgiph7s&_token=uuid_gu7u2346c04kgiph7s_gu7u2346c04kgiph7s5a2d793a31df04.29812695 (the page tries to install add-ons to Firefox - be careful with the site). It seems that the page only is able to hijack the window if it is served from an https server, and not opened locally, but I will attach the html site in case 1) the link above has expired or 2) it otherwise helps to debug the issue.

I am marking as a security issue, as I think that the average user might resort to installing the so called "update" after not being able to close the window (although the window is possible to close with quick enough esc + ctrl-w key combination and a few tries).


Expected results:

It should be possible to close the window regardless of the web page content.