"Faulty data submitted by 3rd party (French airline?) wreaked havoc!" Yeah, sure. Blame 3rd party while your system didn't sanitize input enough, or was tested

"Faulty data submitted by 3rd party (French airline?) wreaked havoc!" Yeah, sure. Blame 3rd party while your system didn't sanitize input enough, or was tested only with valid data vs. fuzzing (if only to help determine how to handle invalid input).