Nmap Security Scanner

This release fixes reverse-DNS bugs that affected it when running on big-endian machines or Windows, and also fixes a rare crash bug. It includes the maximum segment size (MSS) option in TCP packets to be less conspicuous. DragonFly BSD is supported.

This release includes a rewritten (for speed and memory efficiency) port scanning engine, ARP scanning, a new man page, runtime interaction, 'l335 ASCII art, massive version detection improvements, MAC address spoofing, increased Windows performance, 500 new OS detection fingerprints, completion time estimates, a GTK2 frontend, parallel DNS resolution, options for sending bad checksums and limiting retransmissions, source port zero scans, an XSL stylesheet for producing HTML reports, and much more.

This is a pre-release for testing before the
upcoming 4.0 release. Changes since version 3.99
include runtime interaction support for Windows
(it already worked on UNIX), new nmap-mac-prefixis
and nmap-protocols files, an updated (to 6.4)
LibPCRE, and some fixes to enable compilation on
the new Intel-based Macs.

The new runtime interaction system provides time
estimates and verbosity/debugging setting changes
at the tap of a key while Nmap executes. Reverse
DNS resolution has been parallelized with custom
code to speed up large scans. The new
--max-retries option can also improve performance.
The version detection DB has been updated to 3,153
signatures for 381 different service protocols.
The --badsum option helps you detect tricky
firewall/IDS systems. Dozens of fixes and smaller
features have also been added.