net.sniff - rhaidiz/bettercap GitHub Wiki

A network packet sniffer and fuzzer.

Commands

command	description
net.sniff on	Start the packet sniffer.
net.sniff off	Stop the packet sniffer.
net.sniff stats	Print the packet sniffer session configuration and statistics.
net.fuzz on	Enable fuzzing for every sniffed packet containing the sapecified layers.
net.fuzz off	Disable fuzzing.

Parameters

parameter	default	description
net.sniff.output		If set, the sniffer will write captured packets to this pcap file.
net.sniff.source		If set, the sniffer will read from this pcap file instead of the current interface.
net.sniff.verbose	false	If true, every captured and parsed packet will be sent to the events.stream for displaying, otherwise only the ones parsed at the application layer (sni, http, etc).
net.sniff.local	false	If true it will consider packets from/to this computer, otherwise it will skip them.
net.sniff.filter	not arp	BPF filter for the sniffer.
net.sniff.regexp		If set, only packets with a payload matching this regular expression will be considered.
net.fuzz.layers	Payload	Comma separated types of layer to fuzz.
net.fuzz.rate	1.0	Rate in the [0.0,1.0] interval of packets to fuzz.
net.fuzz.ratio	0.4	Rate in the [0.0,1.0] interval of bytes to fuzz for each packet.
net.fuzz.silent	false	If true it will not report fuzzed packets.

Examples

The local-sniffer.cap caplet will sniff, parse and print all packets on the local machine:

events.clear

set net.sniff.verbose false
set net.sniff.local true
# https://biot.com/capstats/bpf.html
# set net.sniff.filter not arp and not udp port 53

net.sniff on

In the wpa_handshake.cap caplet instead, the sniffer is used to capture WPA2 handshakes while the user is deauthing clients:

...
# Sniff EAPOL frames ( WPA handshakes ) and save them to a pcap file.
set net.sniff.verbose true
set net.sniff.filter ether proto 0x888e
set net.sniff.output wpa.pcap
net.sniff on
...

Change 90% of mDNS incoming packets by fuzzing 40% of their payload (will reinject fuzzed packets):

set net.sniff.verbose true
set net.fuzz.rate 0.9
set net.fuzz.ratio 0.4
set net.fuzz.silent false
set net.fuzz.layers Payload
set net.sniff.filter "host 224.0.0.251 and port 5353"
net.fuzz on

Change 100% of WiFi packets by fuzzing 70% of their Dot11InformationElement and Dot11Data layers:

set net.sniff.verbose true
set net.fuzz.rate 1.0
set net.fuzz.ratio 0.7
set net.fuzz.layers Dot11InformationElement, Dot11Data
net.fuzz on