Microsoft has released nine security updates in what researcher called a "smorgasbord" of patches. In total, Microsoft has released fixes for 19 vulnerabilities in Windows itself, as well as in Windows Media Player, Outlook Express, IIS, Office and several other products.

Included in today's patches were five that plugged holes that Microsoft's own software inherited from a buggy code "library," dubbed ATL (Active Template Library), that the company and others rely on to create their programs.

"This is certainly a hodgepodge," said Andrew Storms, director of security operations at nCircle Network Security. "There's no real pattern this month. I'd call it a smorgasbord."

"It's a big pile of messy stuff," said Eric Schultze, chief technical officer at Shavlik Technologies. "Everything is impacted except for Internet Explorer."

Josh Abraham, a security researcher at Rapid7, agreed. "There are a ton of things all over the map here."

Five of the updates were pegged as "critical," the most serious ranking in Microsoft's four-step scoring system, while four were marked "important," the next rating down.

The big story today, agreed security experts, was MS09-037, the update that fixed five vulnerabilities in several Microsoft-made Windows components caused by bugs in ATL.

"This one is just awful," said Abraham, referring to the ATL update.

Schultze, who called the ATL fixes a "whole handful," also ranked MS09-037 at the top of today's list. "There are five individual patches for five individual controls, each used in different [Microsoft] software. It's good that Microsoft's patched this, but it's going to be really difficult for people to patch."

Storms, however, was surprised by the small number of ATL-related patches. "We expected a slew of ATL patches," he said, "although we only got five. But I expect that we'll see more and more ATL bugs from Microsoft in the next couple of months."

Schultze, who once worked at Microsoft, said he had been told by sources inside the company that with the exception of one still-open investigation, today's fixes patch all ATL-related vulnerabilities in software that ships as part of Windows. "They might have it licked," he said, but warned that Microsoft has yet to dig into other ActiveX controls it's crafted that don't ship "in the box," or come on the operating system's installation CD.

The ATL vulnerabilities were introduced when a Microsoft programmer added an extra "&" character to the widely-used library.

Two weeks ago, Microsoft rushed a pair of emergency updates to users that plugged multiple holes in IE and Visual Studio. Those vulnerabilities were traced to ATL.

Another high-profile update is MS09-043, which patches four critical vulnerabilities in Office Web Components (OWC), a set of ActiveX controls that let users publish Word, Excel and PowerPoint documents on the Web, then view them within Internet Explorer (IE).

Last month, Microsoft warned users of attacks exploiting the ActiveX control that displays Excel spreadsheets in IE, but the company was unable to patch it in time to meet the July update schedule. Security experts had predicted that Microsoft would fix the flaw today.

Users should patch the OWC bugs immediately, Abraham argued. "Anything, like this, that's been turned into a Metasploit module and weaponized should be patched as soon as possible," he said, talking about the popular penetration testing framework that both hackers and legitimate security researchers rely on for developing exploits.

Sheldon Malm, Rapid7's senior director of security strategy, urged Windows users to look beyond MS09-037 and MS09-043, the two updates he thought would get the most media attention today. He, as well as Schultze, singled out two other bulletins - MS09-039 and MS09-042 - that patched the Windows Internet Name Service (WINS) and Telnet components, respectively. "On the other end of the spectrum you've got WINS and Telnet," said Malm, who predicted that their updates would be largely ignored, at least initially.