Mozilla Firefox fails to properly perform security checks on "_search" target

ID VU:519317
Type cert
Reporter CERT
Modified 2005-12-22T00:00:00



A vulnerability in Mozilla Firefox may allow a remote attacker to install malicious code on or read protected information from a vulnerable system.


The Firefox web browser features the ability to open a hyperlink in the "search" web panel. Firefox fails to perform adequate security checks on links opened in the web panel. According to the Mozilla advisory on this issue:

Sites can use the _search target to open links in the Firefox sidebar. Two missing security checks allow malicious scripts to first open a privileged page (such as about:config) and then inject script using a javascript: url. This could be used to install malicious code or steal data without user interaction.

Updated versions of the Firefox browser disallow javascript: and data: URIs from being opened in the search Web panel. They also perform an additional security check to prevent privileged pages, such as about:plugins, from being opened in the search Web panel.


A remote attacker may be able to install malicious code on or read protected information from a vulnerable system.



The Mozilla Software Foundation has published Mozilla Foundation Security Advisory 2005-39 in response to this issue. Users are encouraged to review this advisory and upgrade to the versions of the affected software it refers to.


Users who are unable to upgrade to a fixed version of the software are encouraged to disable Javascript in their browsers.

Systems Affected

Vendor| Status| Date Notified| Date Updated
Mozilla, Inc.| | -| 22 Dec 2005
Red Hat, Inc.| | -| 22 Dec 2005
If you are a vendor and your product is affected, let us know.

CVSS Metrics

Group | Score | Vector
Base | N/A | N/A
Temporal | N/A | N/A
Environmental | N/A | N/A


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Thanks to the Mozilla Foundation for reporting this vulnerability. The Mozilla Foundation, in turn, credits Kohei Yoshino with reporting this issue to them.

This document was written by Chad Dougherty and Will Dormann based on information provided by the Mozilla Foundation.

Other Information

  • CVE IDs: CAN-2005-1158
  • Date Public: 15 Apr 2005
  • Date First Published: 20 Apr 2005
  • Date Last Updated: 22 Dec 2005
  • Severity Metric: 18.90
  • Document Revision: 12