The label, which is still trying to crawl out of its rootkit fiasco – where it was discovered that digital rights management software provided by the U.K. firm First4Internet made computers vulnerable to viruses and hackers – recently announced that 5.7 million of its CDs were shipped with anti-piracy software that might cause security problems when those discs are played on computers.

This time the DRM software is MediaMax, which comes from Arizona-based company SunnComm, a long-time supplier of copy protection software for the label. Apparently, the software installs a file on Windows machines that could allow “guest” users to have unauthorized access to computers.

The security breach was discovered by the online digital rights advocacy group Electronic Frontier Foundation, which brought the issue to Sony BMG’s attention. On December 6th, Sony BMG announced that SunnComm had developed a patch to fix the security problem, and urged consumers who bought the affected CDs to download the patch ASAP.

While certainly a serious problem, this Sony BMG copy-protection episode is unrelated to the rootkit fiasco that emerged last month. However, Sony BMG’s latest DRM misfortune will probably add to the diminishing trust among music fans when it comes to labels trying to limit CD copying.

Or, for that matter, some recording artists. In a recent New York Times editorial, Damian Kulash Jr., lead singer for OK Go, denounced copy-protection efforts.

Wrote Kulash: “Conscientious fans, who buy music legally because it’s the right thing to do, just get insulted. They’ve made the choice not to steal their music, and the labels thank them by giving them an inferior product hampered by software that’s at best a nuisance, and at worst a security threat.

“As for musicians, we are left to wonder how many more people could be listening to our music if it weren’t such a hassle, and how many more iPods might have our albums on them if our labels hadn’t sabotaged our releases with cumbersome software.”