The anonymous researcher who claims to have crafted a Mac OS X worm said Tuesday that he or she will report his findings to Apple Inc., but added that the Cupertino, Calif. company "has a very long way to go" on security.

Identified only as the researcher behind the Information Security Sell Out blog, he or she on Sunday announced that a still-unpatched bug in mDNSResponder, a component of Apple's Bonjour automatic network configuring service, could be exploited by a worm. Apple's May security update, dubbed 2007-005, included a fix for the mDNS bug.

"[My worm] is in the same code base, obviously, but that is where the similarity to the recently patched issues ends," said the Info Sec researcher in an e-mail interview. "When Apple fixed the previous issues, they did not take care of the entire code base and there are a lot of bugs there...some are exploitable, like the one I am using, while others are not. But the fact remains that Apple did a horrible job in fixing this package."

According to Info Sec, the worm is fully automated and ready to use. "It would be considered a fully weaponized exploit and fully automated," said the researcher. "This is really no different than other worms we have seen [on the Windows platform]. Other than that, I am not able to give any more details."

Another researcher, however, questioned whether Info Sec crafted the worm in only a few hours, as claimed. "Writing the exploit in one day...unlikely for anything other than a stack overflow," said Dave Aitel, the chief technology officer at Immunity Inc., the Miami Beach, Fla.-based security company best known for its CANVAS penetration testing ("pentest") software. "So most likely he found a stack overflow in mDNS, which is perfectly possible. It is open source, after all."

Info Sec didn't detail the vulnerability, but did emphasize that writing the exploit was a breeze. "The hard part is finding the bug," he or she said. "Once you have found it, it is very easy to exploit. The Bonjour (mDNS) service is UDP [User Datagram Protocol, one of the core Internet protocols] Universal as well, making it even more fun for things like worms."

But like other researchers who have grown tired of claims that Mac OS X is more secure than rival operating systems, Info Sec saved a last shot for Apple. Although he/she will report the new-found vulnerability to Apple at some point, there is no timetable for the moment. "I do believe in being responsible and working with vendors," said Info Sec, "but I also feel that some vendors need to be treated like children and learn lessons the hard way. Apple has a very long way to go when dealing with security issues in their products."

Aitel leaned a bit the same way. In a posting to his DailyDave mailing list Monday in which he pointed out the Info Sec exploit, Aitel said: "I note that 'Infosecurity Sellout' is claiming there is another bug in mDNS which is wormable. This is obviously untrue, since there are no more remote bugs in OS X."

That last line was firmly tongue in cheek, Aitel clarified today in an e-mail. "No, I'm just being funny. OS X is horribly insecure," he said.

In an e-mailed statement, Apple spokesman Anuj Nayar rebutted. "Apple takes security very seriously and has a great track record of addressing potential vulnerabilities before they can affect users," he said.