A Quebec court on Wednesday approved a class action lawsuit settlement over Sony music CDs that installed software on computers without authorization.

The settlement relates to music CDs sold by Sony BMG (Canada) Inc. that included anti-copying software that would be secretly installed on a computer when it was inserted in a CD drive.

The software made it possible for a computer to be hijacked by an attacker or susceptible to a computer virus.

The Quebec Superior Court's approval of the settlement follows a similar ratification by the Ontario Superior Court on Sept. 21.

The software in question was added to Sony music CDs made or sold in Canada over the last three years.

Details of the settlement and eligibility are available at Sony BMG's Canadian website.

Dozens of lawsuits emerged in Canada and the United States after it was revealed that Sony BMG sold millions of copy-protected CDs worldwide that contained software known as Extended Copy Protection (XCP) and MediaMax, which effectively acted as spyware.

The copy protection software uses a computer program called a rootkit to hide the fact that it is running, making it more difficult to disable.

Rootkits are sometimes used by computer attackers and viruses to conceal unauthorized or malicious intrusions into a computer to which they are trying to gain access.

Software keeps running

Security experts say the fact that the copy protection scheme was hidden wasn't harmful, but it remains active even when a CD isn't being played.

At least one computer virus has been written to take advantage of the vulnerability created by the Sony rootkit.

The copy protection program could read and transmit the internet address of a person's computer, which served to identify the user and send the information back to Sony BMG, said Philippa Lawson, executive director of the Canadian Internet Policy and Public Interest Clinic (CIPPIC).

The recording company could then use that information to take legal action against unauthorized file-sharers in Canada, said Lawson, whose group monitors technology-related policy and law-making.

CIPPIC filed complaints about Sony with federal and provincial agencies on Sept. 21.

The complaints said Sony sought to exclude internet protocol addresses from the settlement's agreement not to collect personal information.

About 80,000 music CDs encoded with XCP were sold in Canada, while roughly 1.4 million CDs sold contained MediaMax.

The CDs included music by artists such as Céline Dion, Ray Charles, Kasabian, Sloan, Alicia Keys and Roseanne Cash.

Sony BMG began encoding XCP into music CDs sold worldwide in March 2005, and MediaMax software in 2003.

Details of the rootkit copy protection scheme were revealed on a programmer's blog in October 2005.