A packet sniffer — also known as a packet analyzer, protocol analyzer or network analyzer — is a piece of hardware or software used to monitor network traffic. Sniffers work by examining streams of data packets that flow between computers on a network as well as between networked computers and the larger Internet. These packets are intended for — and addressed to — specific machines, but using a packet sniffer in "promiscuous mode" allows IT professionals, end users or malicious intruders to examine any packet, regardless of destination. It's possible to configure sniffers in two ways. The first is "unfiltered," meaning they will capture all packets possible and write them to a local hard drive for later examination. Next is "filtered" mode, meaning analyzers will only capture packets that contain specific data elements.
Packet sniffers can be used on both wired and wireless networks — their efficacy depends on how much they are able to "see" as a result of network security protocols. On a wired network, sniffers might have access to the packets of every connected machine or may be limited by the placement of network switches. On a wireless network, most sniffers can only scan one channel at a time, but the use of multiple wireless interfaces can expand this capability.
Prevalence and Risk Factors
Using a sniffer, it's possible to capture almost any information — for example, which websites that a user visits, what is viewed on the site, the contents and destination of any email along with details about any downloaded files. Protocol analyzers are often used by companies to keep track of network use by employees and are also a part of many reputable antivirus software packages. Outward-facing sniffers scan incoming network traffic for specific elements of malicious code, helping to prevent computer virus infections and limit the spread of malware.
It's worth noting, however, that these analyzers can also be used for malicious purposes. If a user is convinced to download malware-laden email attachments or infected files from a website, it's possible for an unauthorized packet sniffer to be installed on a corporate network. Once in place, the packet sniffer can record any data transmitted and send it to a command and control (C&C) server for further analysis. It's then possible for hackers to attempt packet injection or man-in-the-middle attacks, along with compromising any data that was not encrypted before being sent.
Proper use of packet sniffers can help clean up network traffic and limit malware infections; to protect against malicious use, however, intelligent security software is required.
Other helpful reads and links related to Packet Sniffers
What is a Packet Sniffer?
Kaspersky
A packet sniffer — also known as a packet analyzer, protocol analyzer or network analyzer — is a piece of hardware or software used to monitor network traffic. Sniffers work by examining streams of data packets that flow between computers on a network as well as between networked computers and the larger Internet.
FAQs
A Packet Sniffer is hardware or software that connects to a network to monitor, analyse, log, and capture all the network traffic.
What is packet sniffing explained? ›
Packet sniffing is a method of detecting and assessing packet data sent over a network. It can be used by administrators for network monitoring and security. However, packet sniffing tools can also be used by hackers to spy or steal confidential data.
What is a packet sniffer quizlet? ›
sniffer. Also known as a packet sniffer. An application that monitors,filters, and captures data packets transferred over a network.
What do packet sniffers involve ____________? ›
Packet Sniffing involves intercepting data packets to gain insights into network activity, such as data source and destination, content, and protocols.
Which of the following describes packet sniffing? ›
Packet sniffing is the practice of gathering, collecting, and logging some or all packets that pass through a computer network, regardless of how the packet is addressed. In this way, every packet, or a defined subset of packets, may be gathered for further analysis.
What does a sniffer do? ›
Sniffers work by capturing internet traffic and analyzing the data streams to uncover the nature — or even the specific contents — of data sent across a network. Just as cars make up road traffic, internet traffic consists of packets of data traveling through a network.
Is packet sniffing good or bad? ›
Packet sniffing attacks can potentially represent a significant threat to network security, involving methods where attackers monitor network traffic to illegally access and manipulate sensitive data. Understanding these attacks is crucial for implementing effective security measures and preventing potential breaches.
Which tool is an example of a packet sniffer? ›
Wireshark
Wireshark can capture and analyze traffic from hundreds of different network protocols, making it a versatile tool for network administrators and security professionals.
What is true about packet sniffer? ›
A Packet Sniffer is a program that can record all network packets that travel past a given network interface, on a given computer, on a network. It can be used to troubleshoot network problems, as well as to extract sensitive information such as Credentials from unencrypted Login Session's.
Why do hackers use packet sniffing? ›
Packet sniffing is a hacking technique that involves collecting data packets that travel through an unencrypted computer network. Packet sniffers monitor the data packets in network traffic, with the aim of intercepting sensitive information (like personal financial details) to sell or use in other attacks.
Challenges with Packet Sniffing Response
It's difficult to spot the hacker because they might look like an authorized user or even a system administrator.
How does sniffing work? ›
Sniffing is a process of monitoring and capturing all data packets passing through given network. Sniffers are used by network/system administrator to monitor and troubleshoot network traffic. Attackers use sniffers to capture data packets containing sensitive information such as password, account information etc.
How are packet sniffers installed? ›
A hardware packet sniffer is a physical device that is plugged into a network. It is plugged into an ethernet port of your network and will ensure that all packets are filtered and read. Because this requires physical access, most hardware packet sniffers are used by network administrators for legitimate purposes.
What is a packet sniffing? ›
A packet sniffer — also known as a packet analyzer, protocol analyzer or network analyzer — is a piece of hardware or software used to monitor network traffic. Sniffers work by examining streams of data packets that flow between computers on a network as well as between networked computers and the larger Internet.
What is an example of active packet sniffing? ›
A DHCP attack is a type of active packet sniffing example used by attackers to gather and modify sensitive data. DHCP is a client/server protocol that assigns a computer an IP address. Along with the IP address, the DHCP server gives configuration data such as the default gateway and subnet mask.
Is packet sniffing eavesdropping? ›
Eavesdropping, also known as sniffing or snooping, relies on unsecured network communications to access data in transit between devices.
What is the difference between packet sniffing and eavesdropping? ›
An eavesdropping attack occurs when a hacker intercepts, deletes, or modifies data that is transmitted between two devices. Eavesdropping, also known as sniffing or snooping, relies on unsecured network communications to access data in transit between devices.
Is packet sniffing the same as IP spoofing? ›
In simple terms, packet Sniffing is listening in on other people's communications. Packet Spoofing is the dynamic presentation of fake network traffic that impersonates someone else. Packet Sniffing is a passive attack since attackers cannot mutilate the system in any way.
