January security patch rolling out to Nexus and Pixel devices
Android 7.1.1 Nougat factory images containing the January security patch are now available for download via Google's developers website. The following devices are now eligible for the January security update: Pixel, Pixel XL, Pixel C, Nexus 6P, Nexus 5X, Nexus Player and Nexus 9 (Wi-Fi).
The January security bulletin that was published at the same time as the factory images offers details of all security vulnerabilities affecting Android devices.
Of all the issues patched by this update, the most severe is a critical security vulnerability that could enable remote code execution on any affected device via multiple methods, including email, web browsing, and MMS when processing media files.
Google also notes that it did not receive any reports of any Android user having been affected by any of these newly reported issues that have been patched in the January security update.
The January security update is rolled OTA (over-the-air), but you can flash the factory images if you don't want to wait for it.