The risk is not in what the law permits but in the fact that it positions the government to act inappropriately with greater ease. Part of the legislation is the formation of an advisory group to develop standards for protecting privacy. However, there is inherent risk. The problem is that the national security risk is also real and needs to be addressed.
By the way, none of these standards apply to machines that are not hosting systems deemed to be critical to security. This, nothing in this bill would give the government access to personal computers. However, given that most software attacks are now launched through Trojans that attack and take over personal computers attached to the Internet, effective defense strategies will ultimately need to improve tools for tracking these attacks back to the hosts that launch them and from there back to the hosts that planted the original Trojans. This may not be possible without forensic assessment of the intermediate machines. These are typically personally owned machines that do not house any critical systems.