Apple on Tuesday released a major security update to address 87 potential vulnerabilities in its applications and Mac OS X operating system.

Apple Security Update 2008-002 fixes a variety of flaws that could allow cross-site scripting, spoofing, privilege escalation, and denial of service attacks, among other forms of attack. It is available through the Mac OS X Software Update control panel or as a download from Apple's Web site.

Earlier on Tuesday, Apple released a new version of its Safari Web browser that addressed 13 security issues. Apple's last major patch, in December 2007, contained more than 40 fixes.

About half of the vulnerabilities repaired by Apple are in open-source applications, including Apache (10 advisories), Clam AV (9 advisories), MIT Kerberos 5 (4 advisories), and PHP (10 advisories). The other half were found in Apple applications or components.

The affected software includes AFP Client, AFP Server, Apache, AppKit, Application Firewall, CFNetwork, ClamAV, CoreFoundation, CUPS, curl, Emacs, file, Foundation, Help Viewer, Image Raw, Kerberos, libc, mDNSResponder, notifyd, OpenSSH, pax archive utility, PHP, Podcast Producer, Preview, Printing, System Configuration, UDF, Wiki Server, and X11.

While Apple doesn't characterize the vulnerabilities by severity, a significant number of them could allow a remote attacker to execute arbitrary code on the affected system.

But such risks remain largely theoretical. As security consultant Rich Mogull put it in an article on the TidBits Web site on Tuesday: "[A]t this point in time, I don't recommend desktop antivirus for the average Mac user." Security software vendors nonetheless would welcome your patronage.