SunnComm MediaMax DRM 5.0.21.0, as used by Sony BMG, assigns insecure Everyone/Full Control permissions to the "SunnComm Shared" directory, which allows local users to gain privileges by modifying programs installed in that directory, such as MMX.exe.
http://www.vupen.com/english/advisories/2005/2783
http://www.securityfocus.com/bid/15754
http://www.kb.cert.org/vuls/id/928689
http://www.eff.org/news/archives/2005_12.php#004234