AWS Network Firewall now supports Amazon Virtual Private Cloud (VPC) prefix lists to simplify management of your firewall rules and policies across your VPCs. Prefix lists enable you to group one or more CIDR blocks into a single object. You can group IP addresses that you frequently use in a prefix list, and reference this list in AWS Network Firewall rule groups. Previously you needed to update individual firewall rules when scaling your network to add new IP addresses, which can be time-consuming and error-prone. Now you can update the relevant prefix list and all AWS Network Firewall rule groups that reference the prefix list are automatically updated. As you scale your network, you can use prefix lists to simplify management of your firewall rule groups and policies across multiple VPCs and accounts in the same AWS Region. You can use AWS-managed prefix lists or you can create and manage your own prefix lists.
Source:: Amazon AWS