Firesheep is a vulnerability exploitation tool that’s used to hijack web sessions, typically over a shared network. It was developed to expose flaws in web application security and it works by capturing cookies from various websites when users log in, allowing unauthorized individuals to access their accounts. It specifically targets unsecured WiFi connections though it’s now largely defunct due to increased SSL usage across many websites.


The phonetics of the keyword “Firesheep” is: /ˈfaɪərʃiːp/

Key Takeaways

  1. Firesheep is a Firefox extension that was designed to demonstrate the security vulnerabilities of HTTP. It simplifies the process of hijacking web sessions, making it easy even for individuals with limited technical knowledge to steal cookies and impersonate other users on various websites.
  2. The second key point about Firesheep is that it has drawn significant attention to the issue of session hijacking. By making the process so straightforward, it has forced many websites and online services to start taking web security more seriously and to implement better safeguards to protect their users.
  3. Lastly, since Firesheep poses such a serious privacy threat, it’s important to protect yourself when using public Wi-Fi networks. Using VPN, enabling HTTPS for every site that supports it, or simply refraining from accessing sensitive websites while on public networks, can help to minimize the risk.


Firesheep became significant in the world of technology due to its ability to exploit security vulnerabilities in web applications, specifically those communicating over non-encrypted HTTP connections. Developed as a free open-source extension for the Firefox web browser by Eric Butler in 2010, Firesheep simplified the process of session hijacking, also known as “sidejacking.” While it raised serious concerns regarding internet security, its existence forced many web services to reinforce their security measures, primarily through the adoption of full-time HTTPS secure connections. By exposing the significant security flaws in well-known platforms, Firesheep stimulated the momentum towards a safer and more secure internet.


Firesheep is a packet-sniffing browser extension utilized for session hijacking. It is primarily designed to work on open Wi-Fi networks by capturing cookies from certain websites to let the user access the sites without a required login. It was created to demonstrate the level of vulnerability that exists in website security, particularly on public, unsecured networks. The primary goal was to show how easily user information could be compromised by anyone with a basic understanding of packet analysis, prompting users and organizations to demand better security measures from popular websites.The purpose of using Firesheep was to raise awareness in both users and web providers about the importance of secure HTTP sessions, known as HTTPS. Firesheep illustrated that an eavesdropper on an unsecured network could swiftly collect unencrypted cookies, allowing them to impersonate other users on social media, online banking, e-commerce platforms, and email providers. While it was not designed as a tool for malicious intent, its easy-to-use interface came with the potential risk of being misused, further highlighting the necessity for fully encrypted web sessions.


Firesheep is an extension for the Firefox web browser that uses a packet sniffer to intercept unencrypted cookies from websites such as Facebook and Twitter, allowing others to gain access to the user’s account. Here are three real-world examples related to Firesheep:1. A user at a public Wi-Fi hotspot: If a person is using public Wi-Fi, such as at a coffee shop or airport, and is logged into a web service like Facebook without secure HTTPS encryption, another person on the same network running Firesheep could potentially access their Facebook account. Firesheep served to highlight the associated risks and lead to increased awareness about the importance of connection security.2. Increased attention to web security: Firesheep significantly raised the general level of attention to web security when it was released in 2010. At this time HTTPS, the secure version of HTTP, was not as widespread as it is today. After Firesheep’s release, many websites, including Facebook and Twitter, responded by making HTTPS the default connection option, greatly increasing the overall security of web browsing.3. An education tool for network security: Firesheep can be used as a tool to educate people about network security. It can demonstrate how an unencrypted Wi-Fi network could be a security risk and can clearly show how a person’s information can be intercepted and used without their knowledge. This educative illustration has led to widespread improvements in connection security and user habits online.

Frequently Asked Questions(FAQ)

Q: What is Firesheep?A: Firesheep is a Firefox extension used for hijacking people’s sessions over wireless networks. Developed by Eric Butler, it demonstrates HTTP session hijacking attacks.Q: How does Firesheep work?A: Firesheep works by sniffing network traffic and intercepting cookies from certain websites as the cookies are transmitted over networks, thus allowing it to capture login sessions.Q: Is Firesheep legal?A: While the use of Firesheep itself is not illegal, using it to access someone else’s accounts without permission could lead to legal consequences.Q: How can I protect myself against Firesheep?A: To protect yourself, consider using secure HTTPS connection for every site that offers it, or use a VPN when browsing on a public wireless network, as Firesheep doesn’t work over these types of connections.Q: What platforms support Firesheep?A: Firesheep is primarily designed for Firefox browsers. Therefore, any platform running Firefox, such as Windows, Linux, or MacOS, can support Firesheep.Q: Do all websites have a vulnerability to Firesheep?A: Not all websites. Only those websites that transmit cookies over unencrypted networks are vulnerable. Websites that utilize HTTPS for all their traffic are typically safe.Q: How do I recognize if I have become a victim of Firesheep?A: It might be hard to directly recognize if you’ve fallen victim, as Firesheep doesn’t visibly alter anything on your system. However, if you notice unfamiliar activities on your online accounts, especially after using public WiFi, there’s a chance you may have been hijacked.

Related Finance Terms

  • Session Hijacking
  • HTTP Unsecured Connection
  • Sidejacking
  • WiFi Eavesdropping
  • Firefox Extension

Sources for More Information


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