This article describes the support for specifying User Defined Fields(UDF) in Port ACLs including IPv4, IPv6, and

4.23.2F Security ACL Port ACL UDF

User Defined Fields (UDFs) are access-list (ACL) filters that consist of an offset into a packet and a pattern to match at the given offset. It can be used to match non-standard fields in a packet that don’t have existing well-defined filter criteria. An example of a non-standard field is bytes at an arbitrary offset within a UDP payload.

TOI Security ACL UDF EOS 4.34.2F