Moscow's Kaspersky Lab has offered more details on the embarrassing hack that hit its US website last weekend.

A hacker, who identified himself only as Unu, said that he was able to break into a section of the company's brand-new US support website by taking advantage of a flaw in the site's programming.

On a conference call with reporters, Kaspersky Senior Research Engineer Roel Schouwenberg said that while he believed that the hacker did not access any customer information such as email addresses, the hack would hurt the company's image.

"This is not good for any company, and especially a company dealing with security," he said. "This should not have happened, and we are now doing everything within our power to do the forensics on this case and to prevent this from ever happening again."

Schouwenberg blamed the breach on a web programming flaw that was introduced in a Januay 29 redesign of the support site, meaning that the bug was live on Kaspersky's site for about 10 days. "Something went wrong in our internal code reviewing process," he said.

This flaw left Kaspersky's support site vulnerable to what's known as a SQL injection attack, which could have given the hacker access to about 2,500 customer email addresses and to perhaps 25,000 product activation codes.

In a SQL injection attack, the hacker takes advantage of bugs in web programs that query databases. The point is to find a way to run commands within the databases and access information that would normally be protected.

Code on Kaspersky's website is typically subjected to an internal and external audit. Kaspersky has hired database expert David Litchfield to investigate the incident and expects to be able to report more on the hack within 24 hours, the company said.

In an email interview, Litchfield said that he has done this type of investigation before. "Typically there are no problems with investigations of this type. Of course, an attacker can attempt to hide their tracks, which makes things more difficult - but by no means impossible."

Unu notified Kaspersky of the bug via email on Friday, and then one hour later hacked into the site. Kaspersky didn't see that email until much later, but the company realised it had been hacked by around noon Eastern Time on Saturday, Schouwenberg said. Just 15 minutes later, Kaspersky reverted to an older version of its support site code, which did not contain the error.

Kaspersky believes that Unu is from Romania, but is not seeking legal action in the case. Romanian authorities have limited resources and are unlikely to investigate the incident further, Schouwenberg said in an email.

Worse attacks have happened. In fact, the Kaspersky hack is "barely even worth mentioning" next to major security breaches, such as the recent hack that gave criminals access to systems at credit-card processor Heartland Payment Systems, said Paul Roberts, an analyst with The 451 Group. "But Kaspersky is a security company, " he said via instant message. "So there's a much bigger reputational risk here than with, say, some supermarket."