Google today released the July 2017 security patch, now rolling out to both Pixel and Nexus devices before it reaches everyone else’s phone. As is the case with many security patches, there are two different levels this month: one is labeled 2017-07-01, while the other is known as 2017-07-05. In total, there are 139 different fixes between the two patches, with the most severe being a “critical security vulnerability in media framework that could enable a remote attacker using a specially crafted file to execute arbitrary code within the context of a privileged process.”
For those of you who hate waiting around for over-the-air updates, you can download factory images and OTA images from their respective links for the Pixel, Pixel XL, Nexus 6P, Nexus 5X, Nexus 6, Nexus 9, Nexus Player, and Pixel C. Google has a nifty little guide on how to flash a factory image to your device here. Just note that if you do so, all of your data will be erased from your phone so be sure to perform a backup first.