US-CERT released a security announcement today that there are security update versions of Firefox (web browser), Thunderbird (email & Usenet news) and SeaMonkey (suite) available today.

Since Netscape is based on the same Gecko engine, users of Netscape are urged to disable Javascript (presumably until a new Netscape version is released).
Quoting Mozilla.org’s site:

As part of Mozilla Corporation’s ongoing stability and security update process, Firefox 1.5.0.8 is now available for Windows, Mac, and Linux for free download from mozilla.com (http://www.mozilla.com/en-US/firefox/all-older.html). We strongly recommend that all Firefox 1.5.x users upgrade to this latest release. This update is available immediately in 37 languages including German, French, Spanish, Japanese, Simplified and Traditional Chinese, Korean, and more.

Note: Firefox 1.5.0.x will be maintained with security and stability updates until April 24, 2007. All users are strongly encouraged to upgrade to Firefox 2

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