Everything you do worth doing is “dangerous” to some degree – but in comparison to other strength & conditioning programs CrossFit is no more or less dangerous. Studies of injury rates have actually shown that injuries are more common in repetitive motion fitness programs (i.e. running only) in comparison to CrossFit. The injury rate for team sports is significantly higher.
Injuries happen in strength sports because the athlete worries more about milestones (such as weight) than their technique or ability is prepared for. They push themselves too hard or cannot yet perform the movement properly. That is why we have coaches that will be actively helping you scale workouts appropriate to your fitness level, strength, and mobility limitations.
Science aside, CrossFit, and our gym in particular, is concerned with technique first and foremost, followed by the consistent use of that technique, long before we increase load (weight) or intensity (speed).