CIDR Matching a subnet in a list of subnets

So IP to a subnet Cidr match has always worked in Splunk. No issues there. BUT a request came where we need to do a subnet to subnet cidr match and other than hacking my way out of it , don’t think the cidrmatch function honors that. Example.. IPCidr = 10.1.1.0/24 Subnetlookup.csv 10.1.0.0/16 10.2.1.0/24 10.2.0.0/16 Cidrmatch doesn’t work when I try to check IpCidr in Subnetlookup,csv.. Moment I change it to 10.1.1.1 it works. Any ideas.. is there any other function which does that?