Yes, there are a handful of malware items, but they can't be installed unless you (the user) provide your Admin password. Browser exploits are few and far between, and are quickly fixed when discovered.
So what? Trojans, by definition, will trick a user into installing them. Just have a look at the numerous posts in these forums around the time of the MacDefender episode.
Here's a "handful" of OS X exploits. From the ClamX catalog:
daily.cvd not-OSX.Tored
daily.cvd OSX.Flashback-1
daily.cvd OSX.Flashback-3
daily.cvd OSX.Flashback-2
daily.cvd OSX.Flashback-4
daily.cvd Trojan.OSX.Miner
daily.cvd OSX.Defma
daily.cvd MacOSX.Revir-1
daily.cvd OSX.BlackHol
daily.cvd OSX.BlackHol-1
daily.cvd MacOSX.iMuler-1
daily.cvd Trojan.OSX.FlashBack.A
daily.cvd OSX.DevilRobber
main.cvd OSX.RSPlug
main.cvd Trojan.OSX.iservices.A
main.cvd Trojan.OSX.iservices.B
main.cvd OSX.DNSChanger.dmg
main.cvd OSX.DNSChanger.dmg-1
main.cvd Trojan.OSX.RSPlug.F.dmg
main.cvd Trojan.OSX.RSPlug.F.dmg-1
main.cvd Trojan.OSX.RSPlug.F.dmg-2
main.cvd Trojan.OSX.RSPlug.F.dmg-3
main.cvd Trojan.OSX.RSPlug.F.dmg-4
main.cvd Trojan.OSX.RSPlug.F.dmg-5
main.cvd Trojan.OSX.RSPlug.G.dmg
main.cvd Trojan.OSX.RSPlug.G
main.cvd Exploit.OSX.Safari
main.cvd Trojan.OSX.Cowhand
main.cvd Backdoor.OSX.BlackHole
main.cvd Trojan.Downloader.OSX
main.cvd OSX.Flashback
main.cvd Trojan.Downloader.OSX-1
main.cvd OSX.DNSChanger
main.cvd OSX.Trojan-2
main.cvd Trojan.OSX.Opener
main.cvd Trojan.OSX.RSPlug.C
main.cvd Trojan.OSX.RSPlug.D
main.cvd OSX.Tored
main.cvd OSX.RSPlug-2
main.cvd Trojan.OSX.OpinionSpy.B
main.cvd Trojan.OSX.OpinionSpy.A
main.cvd Trojan.OSX.MacDefender
main.cvd Trojan.OSX.MacDefender.B
main.cvd Trojan.OSX.MacDefender.C
main.cvd OSX.Defma-1
main.cvd OSX.Defma-2
main.cvd Trojan.OSX.MacBack
main.cvd Trojan-Downloader.OSX.Fav.A
main.cvd Trojan-Downloader.OSX.Fav.B
49 hits for 'OSX'
Browser exploits?
There are numerous exploits via JavaScript, Flash, Reader and Java or other Plug-ins: XSS, clickjacking, drive-by, ClearClick, Clickjacking, malicious pdfs.
NoScript blocks JavaScript, Java, Flash, Silverlight, and other "active" content by default in Firefox. This is based on the assumption that malicious web sites can use these technologies in harmful ways. Users can allow active content to execute on trusted web sites, by giving explicit permission, on a temporary or a more permanent basis. If "Temporarily allow" is selected, then scripts are enabled for that site until the browser session is closed.
Because many web browser attacks require scripting, configuring the browser to have scripting disabled by default reduces the chances of exploitation. Blocking plug-in content as well helps to mitigate any vulnerabilities in plug-in technologies, such as Java, Flash, Acrobat and so on. NoScript will replace these blocked elements with a placeholder icon. Clicking on this icon enables the element.http://en.wikipedia.org/wiki/NoScript#cite_note-cert-3
http://en.wikipedia.org/wiki/NoScript
If you want to be complacent, that's fine by me. Just don't advise everyone else to adopt that attitude and stick their heads in the sand. There are reasonable precautions to take. It may be fine to tell someone they won't install something without their admin pword, but they first need to be educated when not to give that. You are not always dealing here with people who have the benefit of your "vast" experience. And you might, in general, stop patronizing people who come here for advice, with your often rapid fire, ill-considered information.