A man-in-the-middle attack (MiTM) is an attack against a communication protocol where the attacker relays and modifies messages in transit. The parties believe they are talking to each other directly, but in fact both are talking to the attacker.

learn more… | top users | synonyms (1)

110
votes
8answers
11k views

Are “man in the middle” attacks extremely rare?

In http://cdixon.org/2012/02/12/the-iphone-contact-list-controversy-and-app-security/ Chris Dixon makes a statement about web security Many commentators have suggested that a primary security ...
67
votes
5answers
6k views

How can my employer be a man-in-the-middle when I connect to Gmail? [duplicate]

I'm trying to understand SSL/TLS. What follows are a description of a scenario and a few assumptions which I hope you can confirm or refute. Question How can my employer be a man-in-the-middle when ...
45
votes
4answers
4k views

Is there anything preventing the NSA from becoming a root CA?

There are now tons of Certification Authorities (CAs) that are trusted by default in major OS's, many of which are unrecognizable without online lookup or reference. While there have been attempts ...
29
votes
4answers
24k views

What's an easy way to perform a man-in-the-middle attack on SSL?

I'd like to perform a man-in-the-middle attack on SSL connections between clients and a server. Assuming the following: I've got a certificate that the client will accept, via poor cert validation ...
23
votes
3answers
3k views

For an HTTPS web application, is it worthwhile to encrypt the password before POSTing it, to keep a MITM attacker from harversting it?

Our application has recently gone through penetration testing. The test found one critical security breach, which is essentially: The problem: Attacker sets up a WiFi spot. User enters our site ...
20
votes
4answers
899 views

How can a web application protect IE users when this browser doesn't support HSTS?

HTTP Strict Transport Security (HSTS) is a very useful feature at preventing OWASP a9 violations and attacks like SSLStrip which try and prevent the client from making a secure connection. My ...
18
votes
4answers
1k views

Credit card forms on HTTP pages a MITM risk?

The other day, there was a web developer mailing list thread about a fundraiser page. One person noted that the page with the credit card form was HTTP, not HTTPS. In response, one person said that ...
17
votes
5answers
11k views

Can I detect a MITM attack?

Based on this question here: Are "man in the middle" attacks extremely rare? Is it possible to detect man-in-the-middle attacks, and if so, how would one go about it? In addition, what if ...
16
votes
4answers
951 views

Is it possible to boot an encrypted server remotely and securely?

Imagine you have a server that is at a location which is not trustworthy. People might have physical access to the machine who are not supposed to look at the data stored on it. In this scenario I ...
16
votes
4answers
4k views

Options when defending against SSLstrip?

I'm wondering, does anyone have any suggestions to defend against SSLstrip particularly?
15
votes
6answers
2k views

Safe to make a VPN connection over coffee shop WIFI?

On my work laptop I regularly create a VPN connection that I use to remote desktop to our web server. Is this safe to do on a coffee shop where random people are connected to the same wifi network?
15
votes
3answers
770 views

Can a nation-state adversary perform a MITM attack by compelling a CA to issue them with fake certs?

As I understand it, with any encryption system based on a trust chain / CAs (eg SSL, TLS, S/MIME), it would be possible for a nation-state adversary (such as the NSA) to compel the CA to issue them ...
14
votes
5answers
4k views

How safe is SSL? [closed]

If I got an SSL certificate for my website and use an SSL secured connection (HTTPS), is this safe enough to send my login and password data or should I add some encryption or hashing? And how safe ...
13
votes
6answers
5k views

Why is ARP poisoning killing all network activity?

Using ettercap and ARP poisoning, I was able to eavesdrop on other connections, but suddenly I was unable to make any connection to the Internet. To restore Internet connectivity, I had to restart my ...
13
votes
4answers
4k views

Does Tor Hidden Service Protocol provide more threat protection than a standard HTTPS session?

DuckDuckGo is a search engine that has a Tor Exit Enclave and hidden service. This site is focused on the safe, secure searching of its users. Since DNS is not used in Tor, it appears that HTTPS is ...
12
votes
9answers
18k views

Tracking down a rogue access point

Over the course of about a month we have received multiple reports of a rogue access point attempting to intercept traffic. I suspect an attacker is using a wifi pineapple, or similar hardware ...
12
votes
4answers
430 views

How to safely synchronize time over Internet?

All modern OS now keep accurate time by regularly synchronizing time over an untrusted network - Internet. Could an attacker conducting a MITM attack, influence or change the time of a computer while ...
12
votes
1answer
3k views

Is it safe to disable SSH host key checking if key-based authentication is used?

I have some tasks that go like so: Spin up some new EC2 instances (Amazon Web Services) Get them to execute a task Kill them The problem is that they're (seemingly) randomly assigned an IP ...
11
votes
5answers
4k views

Does HTTPS Everywhere defend me against sslsniff-like attacks?

http://www.thoughtcrime.org/software/sslsniff/ If I have a domain on my HTTPS Everywhere list, so that theoretically it could be only visited via an HTTPS connection in my Firefox, then could an ...
11
votes
1answer
723 views

Is Nokia's “institutional MITM” of SSL traffic vulnerable to CRIME attack?

It's recently been in the news that some Nokia phones proxy all traffic, including SSL connections, through a Nokia proxy. This is effectively an "institutional MITM" attack on users those phones. ...
11
votes
2answers
2k views

Is Apple's push notification service implementation vulnerable to a MitM attack

Recently(more info) I've spotted a strange message in the logs on my quite recent, fresh installation of OS X Mavericks 10.9.2 Apr 27 15:26:47 Ivans-MacBook-Pro.local apsd[194]: Unrecognized leaf ...
10
votes
2answers
1k views

How might the U.K. Government's proposed internet surveillance equipment “bypass” encryption?

http://www.channel4.com/news/black-boxes-to-monitor-all-internet-and-phone-data http://rt.com/news/uk-privacy-internet-freedom-186/ 'Black boxes' will be installed by internet services providers ...
10
votes
2answers
516 views

SSH connection attempts from China show different key; is China doing a MITM attack on SSH traffic?

I have a server located in the USA and SSH to it from various places around the world. When I SSH in from a computer I have never used before, I'll see something like this: The authenticity of host ...
9
votes
2answers
786 views

HTTPS login vs MITM attack

http://www.troyhunt.com/2013/05/your-login-form-posts-to-https-but-you.html My question is, if the threat is that someone controls your internet connection and can serve up bad login pages, couldn't ...
9
votes
2answers
12k views

Specific risks of embedding an HTTPS iframe in an HTTP page

I need help listing the specific risks of embedding an HTTPS iframe that enables credit card checkout inside of an HTTP page. Are there security issues with embedding an HTTPS iframe on an HTTP page? ...
8
votes
3answers
3k views

Preventing a spoofing man in the middle attack?

I was humming along with my usual routine of listening to old Defcon videos trying to understand some of the basics of what's going on in the IT Security world, when I came across one explaining man ...
8
votes
3answers
798 views

Is it possible to “protect” against MITM attacks over HTTP?

In a conversation on twitter I warned a site about a security vulnerability. Specifically, the possibility of a MITM (Man in the Middle) attack used to compromise their registration form. The ...
8
votes
5answers
867 views

How do RSA fingerprints protect from MITM attacks?

I understand that RSA fingerprints are used to verify that you are really connecting directly to who you want to connect to, and not someone else posing as that site. Like when you do a git push, it ...
8
votes
1answer
555 views

Is it possible to recognise and prevent MitM attacks on devices which use self-signed SSL certs?

I use both Linux and Windows at work on a large enterprise LAN. The majority of the network configuration is out of my reach. Certain SaaS applications that are hosted locally on the enterprise LAN, ...
8
votes
3answers
710 views

How practical/important is the Lucky Thirteen TLS attack?

I was reading this article which talks about a new attack against TLS being called Lucky Thirteen. It claims to allow repeatable MitM attacks against HTTPS connections. It's described as being fairly ...
8
votes
1answer
15k views

How to spoof a cell phone tower (cell site, base station) — homemade IMSI-Catcher

An answer to a recent question has given me an idea for a school project (security CS program). Also, an active attacker (with a fake base station) can potentially force a mobile phone to use ...
7
votes
6answers
5k views

How would one fully protect himself against man in the middle-attacks?

Imagine I have a computer where all the trafic is being sent through the MitM. How would it be possible to have a secure connection through this setup? In this case it would be OK to design a new ...
7
votes
4answers
1k views

Man-in-the-middle scenario for TLS

Consider the following scenario: You want to securely communicate with a.com and you only trust the VeriSign root certificate. a.com presents a certificate signed by VeriSign with CN=a.com, so you ...
7
votes
2answers
3k views

How to detect the NSA MITM attack on SSL?

As Bruce Schneider reported here... https://www.schneier.com/blog/archives/2013/09/new_nsa_leak_sh.html ...the NSA reportedly performed a MITM attack on a company in brazil and decrypted their SSL ...
7
votes
2answers
682 views

Is it safe to sync private keys between iOS devices using iCloud?

My iOS app has to handle storing private keys for the user. Normally I would just use Keychain Services for this as I would a password, but it would be great if I could sync the keys between the ...
7
votes
1answer
13k views

How does SSLstrip work?

I've been reading up on SSLstrip and I'm not 100% sure on my understanding of how it works. A lot of documentation seems to indicate that it simply replaces occurrences of "https" with "http" in ...
7
votes
2answers
501 views

Why is TLS_FALLBACK_SCSV secure against a MITM attack?

It is recommended, to mitigate POODLE, if SSLv3 cannot be disabled entirely, to make use of TLS_FALLBACK_SCSV, a signaling cipher suite value that indicates that fallback has occurred. The draft ...
7
votes
2answers
6k views

How to thwart sslstrip attack?

I need help understanding the dynamics of an sslstrip attack. I'm using it to test the security of a site that I own. I can successfully sniff the victim (in this case, myself) credentials over the ...
7
votes
1answer
242 views

Are there any reasons why browsers should block mixed passive content by default?

Most browsers block "active" content that's being loaded over HTTP on HTTPS pages. This includes stuff like javascript which can be modified with an MITM and compromise the security of the entire ...
7
votes
2answers
338 views

LTE networks and MITM

2G would leave you vulnerable to spoofed base stations. 3G tried to somewhat fix that using mutual authentication. Now, I tried to check how LTE handles this but I couldn’t find any usefull ...
6
votes
3answers
1k views

Why can't we do MiTM attacks when using secure connection

I have this silly question that is bothering me. When not using secure connection (HTTP for example) cookies can be intercepted and used to connect to the site as if we have the id and password. We ...
6
votes
3answers
2k views

Best tool for testing an SSL connection in my application [closed]

I have developed an application that send binary data between a .NET client and Java server via TCP. I have recently implemented SSL for this connection and would like a way to demonstrate that it is ...
6
votes
2answers
2k views

How to hack a switch connected network with static ARP?

For example, if there is a network with three computers connected to the same switch, Alice, Bob, and Eve. If Alice and Bob add each other on their own ARP list as a static ARP entry, and Eve wants to ...
6
votes
3answers
420 views

How to fuzz proprietary protocol over SSL?

I'm doing vulnerability research on a client/server architecture that uses a custom proprietary protocol sent over SSL (port 443). I need to be able to intercept the traffic, and be able to view it in ...
6
votes
2answers
3k views

arp spoofing protection on LAN

I am a network administrator in company. I read this article eject any wifi device from network with android Some of employers are using mobile phones and company`s wireless network. Theses employers ...
6
votes
2answers
2k views

How can end-users detect malicious attempts at SSL spoofing when the network already has an authorized SSL proxy?

I'm working on one client's network where they have enabled HTTPS authority spoofing on their proxy. This allows them to effectively perform a man-in-the-middle attack to decipher all outgoing ...
6
votes
1answer
141 views

Are there any situations when one can only mount a passive MITM?

This came up while discussing Web & insecure HTTP - Using RSA for encrypting passwords on the client side Is there any such situation possible when requesting an HTTP page where an attacker is ...
6
votes
4answers
311 views

Is webRTC safe against man in the middle attacks?

We are implementing an open source software package (copay, a multisig bitcoin wallet), that uses peerJS, which uses webRTC to allow peer-to-peer communication between browsers. peerJS (and webRTC) ...
6
votes
1answer
149 views

public key distribution from a central server

I'm trying to code up a encrypted communication program. Originally I was thinking that I would use public key cryptography and then I would keep the public keys in a database where users could query ...
6
votes
2answers
1k views

How do I block LinkedIn from extracting data from Microsoft Exchange Server?

LinkedIn now offers the ability to take a real user and password from the end user and connect to Exchange Server for the purpose of importing contacts into their system. (To do this yourself, click ...