libxtables12 binary package in Ubuntu Oracular amd64

 The iptables/xtables framework has been replaced by nftables. You should
 consider migrating now.
 .
 However, even if a given system may be fully running on native nftables,
 there are other reasons why libxtables might be installed. For one, nftables
 itself uses it to be able to display old rulesets that were created using
 xtables extensions (to help folks migrate). Other third-party software might
 also be linked to this library.
 .
 This library being installed in the system should be harmless in any case.
 .
 This package contains the user-space interface to the Netfilter xtables
 kernel framework.

Source package