Apple announced a new release of Safari for Windows and OS X today. In their advisory they note three vulnerabilities for Windows and two for OS X. All of the flaws could cause arbitrary code execution or abnormal termination.
OS X users should click the Apple logo and select Software Update to receive the patched version. Windows users can use Apple's software update program or download Safari directly from http://www.apple.com/safari/download.
Apple also mentions that the new release of Safari 5.0.2 will use an authenticated HTTPS connection to the new Safari Extensions Gallery. This is good news, as it will make it harder for fake extensions to install in Safari and allow Apple greater control over screening extensions.
Mozilla also released updated versions of Firefox, SeaMonkey and Thunderbird, fixing 14 vulnerabilities, 10 of which are critical. Details of the vulnerabilities can be found on Mozilla's security announce web page.
Thunderbird and Firefox can be updated from the Help menu, or directly from http://www.mozilla.org. The latest versions are Firefox 3.6.9 and Thunderbird 3.1.3. Be sure to deploy the updates if you support these products on your network.
While we're on the topic of browser security, another "zero-day" exploit in Internet Explorer was just disclosed by a Google researcher on the Full Disclosure mailing list. Chris Evans posted a proof of concept demonstrating how one can use this IE flaw to send tweets without a visitor's permission. In a very tongue-in-cheek manner, the default tweet is "@scarybeasts would like the IE CSS bug fixed." Chris does not disclose his conversations with Microsoft over the issue other than to mention that he believes they have been aware of the flaw since 2008.
I won't start the great debate over responsible disclosure all over again, but you can listen to Peter Lee and I discussing the topic. We recorded this in response to the disclosure of a zero day for the Windows Help Center flaw by Google's Tavis Ormandy to Full Disclosure two months ago.
Creative Commons image courtesy of miss_rogue's Flickr photostream.