Some vulnerabilities have been reported in Mozilla Firefox, which can be exploited by malicious people to bypass certain security restrictions, conduct spoofing attacks, or compromise a vulnerable system.

1) Multiple errors in the browser and JavaScript engines can be exploited to corrupt memory.

Successful exploitation may allow execution of arbitrary code.

2) The warning dialog displayed when adding or removing security modules via pkcs11.addmodule or pkcs11.deletemodule does not contain enough information. This can be exploited to potentially trick a user into installing a malicious PKCS11 module.

NOTE: This vulnerability does not affect 3.5.x versions.

3) An error exists when processing operations performed on the columns of a XUL tree element. This can be exploited to dereference freed memory via a pointer owned by a column of the XUL tree element.

Successful exploitation of this vulnerability may allow execution of arbitrary code.

4) An error exists when displaying text in the location bar using the default Windows font. This can be exploited to spoof the URL of a trusted site via Unicode characters having a tall line-height.

5) An error in the implementation of the "BrowserFeedWriter" object can be exploited to execute arbitrary JavaScript code with chrome privileges.

Solution
Update to version 3.0.14 or 3.5.3.

Provided and/or discovered by
3) an anonymous researcher, reported via TippingPoint's Zero Day Initiative
2) Dan Kaminsky

The vendor credits:
1) Steve Roussey, Daniel Holbert, Jesse Ruderman, Olli Pettay, toshi, Josh Soref, Martijn Wargers, Carsten Book, and Taral.
2) Jesse Ruderman.
4) Juan Pablo Lopez Yacubian.
5) moz_bug_r_a4.

Changelog
Further details available in Customer Area

Original Advisory
Mozilla Foundation:
http://www.mozilla.org/security/announce/2009/mfsa2009-47.html
http://www.mozilla.org/security/announce/2009/mfsa2009-48.html
http://www.mozilla.org/security/announce/2009/mfsa2009-49.html
http://www.mozilla.org/security/announce/2009/mfsa2009-50.html
http://www.mozilla.org/security/announce/2009/mfsa2009-51.html

ZDI:
http://www.zerodayinitiative.com/advisories/ZDI-09-065/

Dan Kaminsky:
http://archives.neohapsis.com/archives/fulldisclosure/2009-09/0142.html

Deep Links
Links available in Customer Area