> For the complete documentation index, see [llms.txt](https://hackzzz.gitbook.io/welcome/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hackzzz.gitbook.io/welcome/everything-about-and-notes/network-pentesting/sniffing.md).

# Sniffing

## Sniffing intro

* Sniffing is the act of **intercepting and monitoring traffic on a network.** This can be done using software that captures all data packets passing through a given network interface or by using hardware devices explicitly designed for this purpose.

### TCPDump

```bash
sudo tcpdump -i <INTERFACE> udp port 53 #Listen to DNS request to discover what is searching the host
tcpdump -i <IFACE> icmp #Listen to icmp packets
sudo bash -c "sudo nohup tcpdump -i eth0 -G 300 -w \"/tmp/dump-%m-%d-%H-%M-%S-%s.pcap\" -W 50 'tcp and (port 80 or port 443)' &"
```

### tshark

```bash
tshrak -i eth0 # start sniffing
```

### Bettercap

```bash
net.sniff on
net.sniff stats
set net.sniff.output sniffed.pcap #Write captured packets to file
set net.sniff.local  #If true it will consider packets from/to this computer, otherwise it will skip them (default=false)
set net.sniff.filter #BPF filter for the sniffer (default=not arp)
set net.sniff.regexp #If set only packets matching this regex will be considered
```

### Wireshark

{% embed url="<https://www.wireshark.org/>" %}

## PCredz

This tool extracts Credit card numbers, NTLM(DCE-RPC, HTTP, SQL, LDAP, etc), Kerberos (AS-REQ Pre-Auth etype 23), HTTP Basic, SNMP, POP, SMTP, FTP, IMAP, etc from a pcap file or from a live interface.

{% embed url="<https://github.com/lgandx/PCredz>" %}


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