DSniff

Last updated
dsniff
Developer(s) Dug Song
Stable release
2.3 / December 17, 2000;21 years ago (2000-12-17)
Operating system Unix-like
Type Packet sniffer
License 3-clause BSD License [1]
Website www.monkey.org/~dugsong/dsniff/

dSniff is a set of password sniffing and network traffic analysis tools written by security researcher and startup founder Dug Song to parse different application protocols and extract relevant information. dsniff, filesnarf, mailsnarf, msgsnarf, urlsnarf, and webspy passively monitor a network for interesting data (passwords, e-mail, files, etc.). arpspoof, dnsspoof, and macof facilitate the interception of network traffic normally unavailable to an attacker (e.g., due to layer-2 switching). sshmitm and webmitm implement active man-in-the-middle attacks against redirected SSH and HTTPS sessions by exploiting weak bindings in ad-hoc PKI. [2] [3]

Contents

Overview

The applications sniff usernames and passwords, web pages being visited, contents of an email, etc. As the name implies, dsniff is a network sniffer, but it can also be used to disrupt the normal behavior of switched networks and cause network traffic from other hosts on the same network segment to be visible, not just traffic involving the host dsniff is running on.

It handles FTP, Telnet, SMTP, HTTP, POP, poppass, NNTP, IMAP, SNMP, LDAP, Rlogin, RIP, OSPF, PPTP MS-CHAP, NFS, VRRP, YP/NIS, SOCKS, X11, CVS, IRC, AIM, ICQ, Napster, PostgreSQL, Meeting Maker, Citrix ICA, Symantec pc Anywhere, NAI Sniffer, Microsoft SMB, Oracle SQL*Net, Sybase and Microsoft SQL protocols.

The name "dsniff" refers both to the package as well as an included tool. The "dsniff" tool decodes passwords sent in cleartext across a switched or unswitched Ethernet network. Its man page explains that Dug Song wrote dsniff with "honest intentions - to audit my own network, and to demonstrate the insecurity of cleartext network protocols." He then requests, "Please do not abuse this software."

These are the files that are configured in dsniff folder /etc/dsniff/

/etc/dsniff/dnsspoof.hosts
Sample hosts file. [4]
If no host file is specified, replies will be forged for all address queries on the LAN with an answer of the local machine’s IP address.
/etc/dsniff/dsniff.magic
Network protocol magic
/etc/dsniff/dsniff.services
Default trigger table

The man page for dsniff explains all the flags. To learn more about using dsniff, you can explore the Linux man page. [5]

This is a list of descriptions for the various dsniff programs. This text belong to the dsniff “README” written by the author, Dug Song.

See also

Related Research Articles

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Packet analyzer Computer network equipment or software that analyzes network traffic

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Justniffer is a TCP packet sniffer. It can log network traffic in a 'standard' or in a customized way. It can also log response times, useful for tracking network services performances . The output format of the traffic can be easily customized. An example written in Python stores the transferred contents in an output directory separated by domains. This means that the transferred files like html, css, javascript, images, sounds, etc. can be saved to a directory.

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References

  1. LICENSE file in the tarball
  2. dsniff
  3. 1 2 3 4 5 6 7 8 9 Christopher R. Russel. "Penetration Testing with dsniff".
  4. dnsspoof(8) - Linux man page
  5. dsniff(8): password sniffer - Linux man page