The AT&T variant of the LG G5 is receiving a new security update right now. The update is available over-the-air, and brings several security enhancements and bug patches.
If you own the LG G5 on AT&T network, then you may have received the update, or will receive it in the next few days. The software version of the new update is H82020q and it weighs around 60MB. There are no new features in the update, but it is a recommended install.
As per the change-log, the update installs the November Android security patch on your G5. It also includes a fix for the BlueBorne exploit. and patch for the KRACK Wi-Fi vulnerability. So, you see, this is an important update.
Other US carriers, such as Sprint and T-Mobile, have also released similar updates for the LG G5 and other devices recently. Once you receive the update, install it only if your device has more than 50 percent charge!