Steps to reproduce the scenario

1. Set up Insight Discovery as per this doc - Set up Insight Discovery.
2. Configure the IP range in the scan settings with the modifier to scan all the usable IP addresses. For example, 192.168.178.0/23.
3. Start a scan with the scan setting above and observe the number and the list of IP addresses generated.

Actual Results

The number of IP addresses generated is incorrect for all CIDR prefix except /24. 192.168.178.0/23, for instance, has only 508 IP addresses generated and scanned. 192.168.178.255 and 192.168.179.0 are missing.

Here's another example where 1022 IP addresses are expected but only 1016 are generated. All the xxx.xxx.xxx.0 and xxx.xxx.xxx.255 usable IP addresses are excluded from the scan.

1/21/2022 7:20:45 PM : ScanSetting: 00001 with entire Range: 192.168.56.0/22
1/21/2022 7:20:45 PM : Generating list of IP's to scan from range: 192.168.56.0/22
1/21/2022 7:20:45 PM : Getting 1016 IP's to scan.

Workaround

Include the single IP addresses like

192.168.178.0/23;192.168.178.255;192.168.179.0

Suggestion

Automatically include x.x.x.0 and x.x.x.255 when an IP range is specified