A list of the bill's Congressional co-sponsors is a short way down in the comments here; I just sent an email to my representative, who co-sponsored the bill. I encourage you to check if your representative is a co-sponsor, and if so, to contact him or her about this issue. I'll provide my letter as a template.
I write to you as a member of *District*, after learning of your cosponsorship of the Cyber Intelligence Sharing and Protection Act. I am one of many citizens who are concerned about the broad authority given to corporations and the government to collect and share proprietary information about their users in the name of 'cybersecurity', with little oversight or transparency to ensure that these tools are not misused. While I recognize the challenges posed by our open networks, this is a clumsy and overreaching method of developing cybersecurity. I would like to request that you withdraw your support of this bill.
Thank you for your time,