theHarvester is a tool for gathering e-mail accounts, user names and hostnames/subdomains from different public sources. It’s a really simple tool, but very effective.
SEAT (Search Engine Assessment Tool) is the next generation information digging application geared toward the needs of security professionals. SEAT uses information stored in search engine databases, cache repositories, and other public resources to scan a site for potential vulnerabilities. It’s multi-threaded, multi-database, and multi-search-engine capabilities permit easy navigation through vast amounts of information with a goal of system security assessment. Furthermore, SEAT’s ability to easily process additional search engine signatures as well as custom made vulnerability databases allows security professionals to adapt SEAT to their specific needs.
tcptraceroute is a traceroute implementation using TCP packets.
The more traditional traceroute(8) sends out either UDP or ICMP ECHO packets with a TTL of one, and increments the TTL until the destination has been reached. By printing the gateways that generate ICMP time exceeded messages along the way, it is able to determine the path packets are taking to reach the destination.
TCtrace is like itrace a traceroute(1) brother – but it uses TCP SYN packets to trace. This makes it possible for you to trace through firewalls if you know one TCP service that is allowed to pass from the outside.
Protos is a IP protocol scanner. It goes through all possible IP protocols and uses a negative scan to sort out unsupported protocols which should be reported by the target using ICMP protocol unreachable messages.
netmask asks for the netmask by ICMP.
netenum can be used to produce lists of hosts for other programs. It’s not as powerful as other ping-sweep tools, but it’s simple. When giving a timeout, it uses ICMP echo request to find available hosts. If you don’t supply a timeout, it just prints an IP address per line, so you can use them in shell scripts.