hakrevdns

hakrevdns is a lightweight, open-source command-line utility for performing large numbers of reverse DNS lookups efficiently. Written in Go, it converts IP addresses into associated hostnames by querying DNS PTR records. The software accepts lists of IP addresses through standard input, making it suitable for integration with other network reconnaissance tools. Its concurrent processing architecture allows multiple DNS requests to run simultaneously. Users can adjust thread counts, specify custom DNS resolvers, and load resolver lists from files. It supports both UDP and TCP DNS queries and can use system default resolvers. Results associate discovered hostnames with their corresponding IP addresses. The tool helps security researchers and network administrators identify domains, subdomains, and infrastructure associated with authorized IP address ranges.