Nighthawk is an experimental implementation of ARP/ND spoofing, password sniffing and simple SSL stripping for Windows.

It requires WinPcap and .NET Framework 4 (Client profile) and works best on Vista & Windows 7.

Features:

    ARP spoofing (IPv4) and RA spoofing (IPv6) over local network
    Password sniffing for most common HTML form fields (name-based matching), HTTP basic authentication, FTP, POP3, SMTP, IMAP
    Basic SSL stripping (doesn't work on HTTPS-only sites) and cookie stripping
    Quick attack mode
    Windows Phone application for remote access to sniffer results (HawkWP)

Changelog:

    Nighthawk 0.9.4 (RC)
        Windows 8 support
        bug fixes
        WCF service removed due to instability
    Nighthawk 0.9.3 (RC)
        fixed some WCF service related issues
        updated HawkWP to 1.1
            lots of bugs fixed, cleaner GUI
    Nighthawk 0.9.2 (RC)
        added a simple WCF service for remote access to sniffer results (see Downloads for a WP client)
    Nighthawk 0.9.1 (RC)
        updated SharpPcap to version 4.0.0
        added NBug for better crash reporting
    Nighthawk 0.9 (RC)
        fixed scanning of large subnets
        fixed a crash when WinPcap not installed
        updated SharpPcap to version 3.7.0
        added "Quick attack" mode

Crash reporting:

From version 0.9.1 onwards you'll now see a new exception window after Nighthawk crashes. If you click on "Send and quit" button, a .ZIP file containing some basic debug information will be created (nothing will actually get sent!) and you can attach it to a bug report to help me fix the problem.

Disclaimer:

This software may be used only for educational and security testing purposes with your network administrator's consent. The author takes no responsibility for improper (or even illegal) usage, data loss or other damage that might occur during its usage.