https://wccftech.com/november-security-patch-rolling-out-to-pixel-nexus-devices/

The November security patch marks the third update to Android 9 Pie-powered devices since its release. It is the first for the Pixel 3 and Pixel 3 XL that launched last month. There are 17 issues resolved in the November security patch dated 2018-11-01 and 19 for 2018-11-05. Vulnerabilities range from high to critical, with the most severe relating to the media framework and a remote attacker possibly executing arbitrary code through a crafted file.

Additionally, this marks the end of security updates for the Nexus 5X, Nexus 6P, and Pixel C since they’re no longer supported. They still might get quarterly updates, depending on the nature of the vulnerabilities.  Google notes that there are no reports of customers being affected by these security issues. The company cited in its 2017 year in review of Android security that 30% more devices are getting patches compared to the prior year.