Are there universities that consider it academic misconduct for students to publish material created by faculty?
Since you asked for norms at other schools, here is one data point: UC Berkeley has an explicit policy on this subject.  At UC Berkeley, instructors own the copyright on their course materials and are allowed to specify the policy on dissemination.  In additional, dissemination for a commercial purpose is prohibited without express consent of the instructor.  If instructors specify a policy, students who violate this policy can be punished for academic misconduct -- and this is stated explicitly in the UC Berkeley policies.

In more detail, UC Berkeley's policy on Course Note-Taking and Materials states:


  Individual instructors retain copyrights to [...] class materials they create.  Instructors may permit, limit, or prohibit the [..] further distribution of class materials created by an instructor (class notes, recordings, exams, and class materials, collectively referred to as “Class
  Materials”).  Instructors are encouraged to clearly communicate their preferences on recording and sharing Class Materials in their syllabi. [...]
  
  Unauthorized use of Class Materials may subject an individual to legal proceedings brought by the instructor as well as disciplinary and legal proceedings by the University. [...]


Thus, if an instructor states in the syllabus that dissemination of exams is not allowed, then a student who violates that restriction may be disciplined by the University for academic misconduct.  On the other hand, if the instructor does not state any policy, and the students shares the exam with others (for non-commercial purposes), there is no violation of University academic misconduct rules, though there might well be a violation of copyright law.

Also, UC Berkeley's Code of Student Conduct has a section that deals specifically with this subject.  It states:


  102.23 Course Materials
  
  Selling, preparing, or distributing for any commercial purpose course lecture notes or video or audio recordings of any course unless authorized by the University in advance and explicitly permitted by the course instructor in writing. The unauthorized sale or commercial distribution of course notes or
  recordings by a student is a violation of these Policies whether or not it was the student or someone else who prepared the notes or recordings.
  
  Copying for any commercial purpose handouts, readers or other course materials provided by an instructor as part of a University of California course unless authorized by the University in advance and explicitly permitted by the course instructor or the copyright holder in writing (if the instructor is not the copyright holder).


Exams count as course materials and thus are covered by this policy.



Personal opinion: I think sites like CourseHero are scummy, sleazy sites: the worst of the worst.  They require students to submit additional course materials to view the ones that are on record there, and they make no attempt to validate that students have permission to share those course materials; indeed, they have every incentive not to validate whether the student has authorization, and every incentive to encourage unauthorized uploading.  Thus, their business model is based upon encouraging students to share stuff they might not have permission to -- and they profit off of this.  I find this business practice reprehensible and worth of condemnation.

However... it is a separate question whether student use of those sites constitutes academic misconduct.  Personally, I would say that students have a due process right to be informed of their responsibilities, and to only be published for actions that are a clear violation of published policies.  Therefore, I believe it is the instructors' responsibility to establish clear policies -- either on a course-by-course basis, on course syllabi, or else by adopting clear policies at the campus level.  In the absence of such policies, I would be very hesitant to punish students who shared exams with others.  That does not feel fair to me.