If you're using a Samsung Galaxy Note 5 on AT&T, you'll want to keep an eye out for a security update that's rolling out to the smartphone now. According to AT&T's support pages, the update just started rolling out to the carrier's Galaxy Note 5, bringing along unnamed security and performance enhancements.
While AT&T's release notes don't specifically call it out, a screenshot posted by Android Central forum user Bpschoon81 shows that this latest update brings the handset's security patch level up to February 1. As for size, the update looks to come in right around 49MB large.
As the update only just began rolling out, it could take some time to land for everyone.