When you entrust sensitive information to a contracted company or individual, you are also accepting risk. If you do not perform due diligence to ensure your contractor has effective safeguards in place, and understands that your information is sensitive, and if you do not have specific security requirements within your contract, you are opening yourself up to a major embarassment, major incident, or both.
The U.S. State Department entrusts many of their secrets to many different contractors. They have found themselves with yet some more bad press as a result of one of their contractors.