There are some questions on the SF-86 Questionnaire for National Security Positions that are specifically oriented toward professional behavior as well as the use of information technology systems. Based on the examples in your question, I would suspect that you would likely have to answer 27.1 or 27.3 in the affirmative, and provide specific details regarding the events in question.
Question 13C:
Have any of the following happened to you in the last seven (7) years at employment activities that you have not previously listed?
...
Received a written warning, been officially reprimanded, suspended, or disciplined for misconduct in the workplace, such as a violation of a security policy?
Answering in the affirmative requires that you complete a question in 13A to detail the event. Previous questions also require references at employers in the past 7 years, and your work behavior is likely to come up in contact with those references.
Question 27.1:
In the last seven (7) years have you illegally or without proper authorization accessed or attempted to access any information technology system?
Question 27.2:
In the last seven (7) years have you illegally or without authorization, modified, destroyed, manipulated, or denied others access to information residing on an information technology system or attempted any of the above?
Question 27.3:
In the last seven (7) years, have you introduced, removed, or used hardware, software, or media in connection with any information technology without authorization, when specifically prohibited by rules, procedures, guidelines, or regulations or attempted any of the above.
Falsifying this form is likely to be far, far more damaging than answering yes to any of these questions. I'm not sure that one of these will entirely remove your eligibility. I don't have a link handy, but the results of some clearance adjudication reviews for contractors are actually posted. You'd probably be surprised at what gets approved, as long as you properly disclose it.
About the same as the difference between a weekend paintball player and a SF operator (Delta/SAS etc)
– Pepone Jun 19 '14 at 11:49