After confirming earlier today that Android 6.0.1 is now rolling out to Nexus devices with December’s security patches in tow, Google has detailed exactly which security issues this month’s update addresses.

The December 2015 security update patches up 16 issues, 4 of which are designated by Google as “Critical,” 10 of which are “High,” and 2 of which are classified as “Moderate.” The most severe vulnerability was one that could’ve allowed code to be remotely executed on a device when processing a media file through email, MMS, web browsing, and other methods.

For more details on the 15 other security issues addressed in December’s security update, you can check out Google’s Nexus Security Bulletin.

Google first announced its commitment to providing monthly security updates back in August. Android has long been criticized for having security problems, and whether or not you agree with that criticism, you have to agree that these monthly security updates are a good thing for Android as a whole. Several Android manufacturers have since made similar monthly security update commitments, including BlackBerry, which already pushed December’s security update to the Priv.