Mozilla Foundation Security Advisory 2006-29

Spoofing with translucent windows

Announced
April 13, 2006
Reporter
moz_bug_r_a4
Impact
Moderate
Products
Firefox, SeaMonkey
Fixed in
  • Firefox 1.5.0.2
  • SeaMonkey 1.0.1

Description

An interaction between XUL content windows and the new faster history mechanism in Firefox 1.5 caused those windows to become translucent. This could be used to construct spoofs that could trick users into interacting with browser UI they can't see. It's possible a clever game-type presentation could persuade an unsuspicious user into some combination of actions that would result in running the attacker's code.

Firefox 1.0 and the Mozilla Suite 1.7 are not vulnerable.

Workaround

Disable the faster back/forward history:

  1. Enter "about:config" into the location bar and hit Enter
  2. Enter "sessionhistory" into the "Filter" text box
  3. Double-click on browser.sessionhistory.max_total_viewers
  4. Change the default "-1" to "0" and hit the OK button

References

Exploit code and details embargoed during the active update period.