If the driver of the car was at fault and has insurance, you should be covered by his or her insurance. You may be entitled to pain and suffering and expenses related to your injuries from the multiple vehicles involved as well as the car you were in.
Since you are the passenger, you would not be considered at fault unless you grabbed the steering wheel, distracted the driver, or assaulted the driver.
However, if you get into an auto accident in someone else’s car and you do not have insurance, it will depend on the car owner’s insurance policy as to whether or not you are covered. If you have insurance, it’s not a problem or if you are not at fault and the other driver was, it shouldn’t be a problem.
However, don’t for a moment think that since it wasn’t your car that you won’t have a blemish on your driving record. The accident will follow the driver. The car owner’s insurance company may still pay for the damage if you carry collision coverage on your own policy providing you have car insurance. The car owner may see rates increase because of the claim, but would not have an at fault accident on his or her record.