Vulnerability Note VU#575969

Mozilla may process content-defined setters on object prototypes with elevated privileges

A setter is a method in JavaScript that sets the value of a property.

The problem

The setters in Mozilla are called by privileged user interface (UI) code. This elevated privilege can be passed on to the content-provided JavaScript code. Mozilla Firefox and Thunderbird are reported to be vulnerable.

II. Impact

Refer to Mozilla Foundation Security Advisory 2006-37 for fixed versions of Mozilla products.

Disable JavaScript

This vulnerability can be mitigated by disabling JavaScript.

Systems Affected

http://www.mozilla.org/security/announce/2006/mfsa2006-37.html
https://bugzilla.mozilla.org/show_bug.cgi?id=330773
http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Guide:Creating_New_Objects:Defining_Getters_and_Setters
http://www.securityfocus.com/bid/18228

Credit

Thanks to the Mozilla Foundation Security Advisory for reporting this vulnerability, who in turn credit Paul Nickerson and moz_bug_r_a4.

This document was written by Will Dormann.

Other Information

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