Computer Fraud and Abuse Act a of 1986 - Amends the Federal criminal code to change the scienter requirement from "knowingly" to "intentionally" for certain offenses regarding accessing the computer files of another. Revises the definition of "financial institution" to which the financial record provisions of computer fraud law apply. Applies such provisions to any financial records (including those of corporations and small businesses), not just those of individuals and certain partnerships. Revises the criminal liability of persons who exceed authorized access to Federal computers. (Makes the basic offense trespass. Removes the coverage of authorized accessors who exceed their authorization, but without "intent to defraud.") Creates new Federal criminal offenses of: (1) property theft by computer occurring as part of a scheme to defraud; (2) altering information in, or preventing the authorized use of, a Federal interest computer; and (3) trafficking in computer access passwords. Eliminates the special conspiracy provisions for computer crimes. (Such conspiracies shall be treated under the general Federal conspiracy statutes.) Amends penalty provisions to remove the cap on fines for certain computer crimes. Exempts authorized law enforcement or intelligence activities.