When a hacker going by the name Chujwamwdupe published attack code that exploited a recently patched bug in Microsoft Office 2003 earlier this week, it looked almost as if he were publishing the software out of spite.

At the top of his submission, Chujwamwdupe wrote about an e-mail informing him that "Unfortunately, Microsoft has refused to credit you using the name you requested."

"What's wrong with 'chujwamwdupe', eh?" the hacker asked.

Well quite a lot, it turns out, if you live in Poland, where it refers explicitly to a form of sexual intercourse.

In the hacker world, where so much rides on reputation, Microsoft had been put into a tough position. The company generally goes out of its way to credit hackers who responsibly disclose software vulnerabilities, and by not crediting Chujwamwdupe, it may have put customers at risk by accelerating the release of attack code. After all, quickly releasing an exploit is the one way a hacker can back up his claim that he actually discovered the bug in question.

Even though the flaw, which lies in the Works File Converter, was patched the day before the exploit code was released, it will be months before all of Microsoft's customers install the updates. This means that Chujwamwdupe's code could be misused by criminals.

A member of Microsoft's security team flagged Chujwamwdupe's submission, a spokeswoman with Microsoft's public relations firm said in an e-mail message. "One of them happened to speak the right language and brought the issue to our attention," she said. "The finder's user name could have been perceived as offensive in another language, so we credited the vendor, VeriSign iDefense VCP, [Vulnerability Contributor Program] for reporting the issue to us responsibly."

VeriSign pays hackers like Chujwamwdupe for vulnerability information so that it can give its customers better information on the bugs when Microsoft finally patches them. And while the majority of contributors use their real names, some do use hacker pseudonyms.

Usually that's not a problem, said Matthew Richard, the director of iDefense's Rapid Response Team. "It really doesn't come across that often. There really aren't that many handles that are offensive," he said. Chujwamwdupe is "one of the very few that I've seen," he added.

3Com's TippingPoint division, which also pays hackers for vulnerability information, had to talk researcher Manuel Santamarina Suarez out of using a similarly offensive pseudonym, telling him, "we totally get your originality, but we're professionals here," said Terri Forslof, TippingPoint's manager of security research.

According to Forslof, who spent four years working for Microsoft's Security Response group, there are technical reasons why offensive terms cannot be included in the security bulletins. Such a word might cause the bulletin to be blocked by e-mail or Web-filtering software, she said, making it harder for Microsoft to communicate vital security information with its customers.

Still, things would have probably worked out better for all parties if Microsoft and VeriSign had worked out some way to credit the hacker, she said. "If Microsoft would have credited him, would he have felt the need to post that exploit code?"

"I believe that there was a communication breakdown here," she said.