"Microsoft has warned that attackers are actively targeting a security vulnerability in the SafeDisc DRM technology that ships as part of Windows. The problem affects the 'secdrv.sys' file, a component of the SafeDisc copy encryption developed by Macrovision and sold to game developers.
The DRM technology is bundled with Windows Server 2003, Windows XP and Windows Vista, but does not affect Windows Vista. Danish security website Secunia rates the vulnerability as 'less critical', the second step on a five step severity scale. The risk to end users is limited because a successful exploit requires attackers to have an account on the targeted system."