Man-in-the-middle attack

In cryptography and computer security, a man-in-the-middle attack (often abbreviated to MITM, MitM, MIM, MiM or MITMA) is an attack where the attacker secretly relays and possibly alters the communication between two parties who believe they are directly communicating with each other. One example is active eavesdropping, in which the attacker makes independent connections with the victims and relays messages between them to make them believe they are talking directly to each other over a private connection, when in fact the entire conversation is controlled by the attacker. The attacker must be able to intercept all relevant messages passing between the two victims and inject new ones. This is straightforward in many circumstances; for example, an attacker within reception range of an unencrypted Wi-Fi wireless access point, can insert himself as a man-in-the-middle.[1] Example of an attack[edit] Illustration of man-in-the-middle attack. Suppose Alice wishes to communicate with Bob. 1.

How Safe is SSL from MITM (Man In The Middle) Attacks? Website Technology Issues forum at WebmasterWorld The topic of SSL security on an unsecured wifi connection was brought up on on the thread about How to Secure Wordpress Sites [webmasterworld.com] and it seemed there was enough FUD swirling around this topic to start a new thread. This is intended to be educational for those that think SSL-MITM isn't possible so don't shoot the messenger as this is an educational and informative post. I'm not trying to show anyone how to launch a MITM attack, or give away all the steps required to sniff SSL. Besides, there's no need to do this because all of this information is freely available all over the internet with a simple query. From the WordPress thread mentioned above: If you can establish yourself as the MITM (Man in the Middle) you only need to dnsspoof the destination and issue a fake SSL cert as a response to the victim and then you can use SSLDUMP to decrypt the SSL stream. Wow, that was hard wasn't it? Let's do a simple diagram of how that works: The big challenge is getting in the middle.

Public key infrastructure Diagram of a public key infrastructure A public key infrastructure (PKI) is a set of hardware, software, people, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates.[1] In cryptography, a PKI is an arrangement that binds public keys with respective user identities by means of a certificate authority (CA). The user identity must be unique within each CA domain. The third-party validation authority (VA) can provide this information on behalf of CA. The binding is established through the registration and issuance process, which, depending on the assurance level of the binding, may be carried out by software at a CA or under human supervision. Design[edit] Public key cryptography is a cryptographic technique that enables users to securely communicate on an insecure public network, and reliably verify the identity of a user via digital signatures.[2] A PKI consists of:[4][6][7] Methods of certification[edit] Certificate authorities[edit]

How to Create Totally Secure Cookies Securing cookies and sessions is vital to keeping an application secure. Many tutorials have been written on the subject, but as the internet (and browsers loading it) evolve so do the methods you can use to keep your application secure. In this article we’re going to break down the various components of a cookie and what they mean for security. This will include limiting the cookie to certain domains and paths on those domains, choosing what information to store, and protecting the cookie from cross site scripting exploits. In a second article we will go into more depth in how to protect everyone’s favorite cookie, the session ID. How Cookies Work Cookies are simply key/value pairs that let us get around HTTP being a stateless protocol. When the server wants to set a cookie it passes back a header named “Set-Cookie” with the key-value pair and some options. On subsequent requests the client will send along its own header to let the server know the name and value of its stored cookies.

Chapter 14 - Encrypting network traffic (Virtual Private Networks) with IPSec By Kurt Seifried, kurt@seifried.org, Copyright Kurt Seifried With sensitive data moving across public networks some form of encryption is needed to protect the data, provide authentication, and prevent spoofing/etc. The emerging standard for this problem is IPSec (IP Security), which has broad industry support and a recognized set of RFC's laying down the rules. Unfortunately one of the major areas of IPSec is key management, and this is one area where many vendors have trouble interoperating, so if you are considering a hetrogenous network do plenty of testing beforehand. The good news is most vendors support IPSec, many "out of the box", and there are numerous free to cheap clients for Windows 95/98/NT (2000 has built in support). The first decision needed when implementing IPSec is to decide what traffic you want to encrypt. [ Back | TOC | Forwards]

Session management In computer science, in particular networking, a session is a semi-permanent interactive information interchange, also known as a dialogue, a conversation or a meeting, between two or more communicating devices, or between a computer and user (see Login session). A session is set up or established at a certain point in time, this process is called sessionization, and torn down at a later point in time. An established communication session may involve more than one message in each direction. An established session is the basic requirement to perform a connection-oriented communication. Communication sessions may be implemented as part of protocols and services at the application layer, at the session layer or at the transport layer in the OSI model. HTTP/1.0 was thought to only allow a single request and response during one Web/HTTP Session. Most client-server sessions are maintained by the transport layer - a single connection for a single session.

SSH File Transfer Protocol In computing, the SSH File Transfer Protocol (also Secure File Transfer Protocol, or SFTP) is a network protocol that provides file access, file transfer, and file management functionalities over any reliable data stream. It was designed by the Internet Engineering Task Force (IETF) as an extension of the Secure Shell protocol (SSH) version 2.0 to provide secure file transfer capability, but is also intended to be usable with other protocols. The IETF Internet Draft states that even though this protocol is described in the context of the SSH-2 protocol, it could be used in a number of different applications, such as secure file transfer over Transport Layer Security (TLS) and transfer of management information in VPN applications. This protocol assumes that it is run over a secure channel, such as SSH, that the server has already authenticated the client, and that the identity of the client user is available to the protocol. Capabilities[edit] History and development[edit] Version 3[edit]

Secure Shell Secure Shell (SSH) is a cryptographic network protocol for secure data communication, remote command-line login, remote command execution, and other secure network services between two networked computers. It connects, via a secure channel over an insecure network, a server and a client running SSH server and SSH client programs, respectively.[1] The protocol specification distinguishes between two major versions that are referred to as SSH-1 and SSH-2. The best-known application of the protocol is for access to shell accounts on Unix-like operating systems, but it can also be used in a similar fashion for accounts on Windows. Definition[edit] SSH uses public-key cryptography to authenticate the remote computer and allow it to authenticate the user, if necessary.[1] There are several ways to use SSH; one is to use automatically generated public-private key pairs to simply encrypt a network connection, and then use password authentication to log on. Key management[edit] Usage[edit]

SOCKS SOCKS performs at Layer 5 of the OSI model (the session layer, an intermediate layer between the presentation layer and the transport layer). History[edit] The protocol was originally developed/designed by David Koblas, a system administrator of MIPS Computer Systems. The SOCKS reference architecture and client are owned by Permeo Technologies,[2] a spin-off from NEC. Usage[edit] SOCKS is a de facto standard for circuit-level gateways. Another use of SOCKS is as a circumvention tool, allowing traffic to bypass Internet filtering to access content otherwise blocked, e.g., by governments, workplaces, schools, and country-specific web services.[7] Some SSH suites, such as OpenSSH, support dynamic port forwarding that allows the user to create a local SOCKS proxy.[8] This can free the user from the limitations of connecting only to a predefined remote port and server. Comparison to HTTP proxying[edit] SOCKET[edit] HTTP[edit] Bill wishes to download a web page from Jane, who runs a web server.