Your system may not meet the requirements for Firefox, but you can try one of these versions:

Your system doesn't meet the requirements to run Firefox.

Your system doesn't meet the requirements to run Firefox.

Please follow these instructions to install Firefox.

Firefox Privacy Notice

Mozilla Foundation Security Advisory 2006-37

Remote compromise via content-defined setter on object prototypes

June 1, 2006
Paul Nickerson, moz_bug_r_a4
Firefox, SeaMonkey, Thunderbird
Fixed in
  • Firefox
  • SeaMonkey 1.0.2
  • Thunderbird


Paul Nickerson discovered that content-defined setters on an object prototype were getting called by privileged UI code, and moz_bug_r_a4 was able to develop an exploit PoC that demonstrated that the higher privilege level could be passed along to the content-defined attack code.

Thunderbird shares the browser engine with Firefox and could be vulnerable if JavaScript were to be enabled in mail. This is not the default setting and we strongly discourage users from running JavaScript in mail.


Disable JavaScript until an upgraded version is installed. Do not enable JavaScript in mail clients such as Thunderbird.


Exploit details withheld until sufficient time has passed to give users a chance to upgrade