Kaiser Permanente Health Plan, Inc of Northern California disclosed a misconfiguration error on kp.org during a website upgrade on October 12, 2016. For approximately two hours, protected health information (PHI) viewed by signed-in members may have been mistakenly visible to other visitors. The error was repaired by 1:43 a.m. on October 13, 2016. No Social Security numbers or banking information were disclosed. The organization is updating testing procedures for website updates.