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.

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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 ...
126
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8answers
15k views

Are “man in the middle” attacks extremely rare?

In "Some thoughts on the iPhone contact list controversy and app security", cdixon blog Chris Dixon makes a statement about web security Many commentators have suggested that a primary security ...
78
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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 ...
58
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3answers
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Why aren't IMSI catchers rendered ineffective by standard MITM defenses?

There's been a lot of reporting in the past few years about law enforcement agencies using IMSI catchers (also known as Stingrays after a popular brand of them) to intercept cellular communications. ...
43
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How does someone become a man in the middle?

As I understand it in order to commit a succesful MiTM attack you need to be "sitting" somewhere along the traffic path. I assume this means being hooked up to one of the nodes inbetween the end ...
42
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Is it common practice for companies to MITM HTTPS traffic?

My company has just introduced a new VPN policy whereby once connected all traffic is routed the company network. This is to allow for improved monitoring of data theft. It would appear that this ...
40
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4answers
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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 ...
36
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3answers
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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 ...
32
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4answers
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Can or should whitelisting replace encryption?

I've noticed that there is a third-party webservice we utilize programmatically at my job to transmit somewhat sensitive information and I was surprised to see that the endpoint was only using http, ...
26
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3answers
4k 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 ...
24
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5answers
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What prevents a man in the middle from requesting a certificate for your server?

Let's say you have a server at shop.example.com and you are requesting a certificate from some trusted CA like Comodo (they say they'll issue it within few minutes online). First of all, how can ...
23
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Superfish vs. Corporate MITM

I work for a consulting company, and I have been implementing a tool from a security vendor, which is a cloud proxy for all user traffic. It will perform malware scanning and filtering of all web ...
23
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How can a web application protect users when the 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. This ...
23
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5answers
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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 ...
22
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6answers
7k views

Possibility to sniff HTTPS traffic on devices without installing a certificate

My goal is to sniff the HTTPS traffic of some digital devices (AppleTV, game consoles, etc.), and decrypt the HTTPS packets in my local network. I cannot figure out a way by using some HTTPS ...
21
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7answers
5k 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?
20
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4answers
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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 ...
19
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4answers
2k 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 ...
19
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2answers
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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 ...
18
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3answers
950 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 ...
18
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4answers
7k views

Options when defending against SSLstrip?

I'm wondering, does anyone have any suggestions to defend against SSLstrip particularly?
17
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2answers
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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? ...
16
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5answers
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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 ...
16
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Broken SSL on every website [duplicate]

One of my friends called me saying every website anyone in her family goes to has untrusted SSL certificates. From any computer in her house, HTTPS is broken and Firefox or Chrome asks to add an ...
16
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4answers
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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 ...
15
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8answers
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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 ...
14
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6answers
4k views

Does the US government protect its physical internet lines in the US?

It seems like there are lots of ways to prevent man in the middle attacks. I've read many on here and on the rest of the internet. According to wiki you need a secure channel as well to completely ...
14
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9answers
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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 ...
14
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2answers
6k 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 ...
13
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1answer
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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 ...
12
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6answers
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Is it possible for corporation to intercept and decrypt SSL/TLS traffic? [duplicate]

I found there are some companies claim that they offer service that can eliminate SSL/TLS blind spot, such as Blue Coat and Gigamon. Are they talking about some way of decipher the https content ...
12
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5answers
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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 ...
12
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4answers
556 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
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1answer
783 views

Kaspersky Antivirus “secure connection scan” as broken as Superfish?

I've read a lot about Superfish (and similar ad-ware) lately and I basically understand the vulnerability to MITM attacks. But I'm actually wondering if the "secure connection scan" by Kaspersky ...
12
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2answers
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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 ...
12
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1answer
153 views

How can mobile sign-on be secured from imposter authentication screens?

History seems to have come almost full circle where old issues are shown in new/emerging technologies. Background If you trust the operating system, Windows originally had the Control - Alt - Delete ...
11
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2answers
816 views

How long can X.509 certificate chains be?

Usually, I only see certificate chains with a root CA, an intermediate one, and a third one for the particular SSL/TLS website; but can X.509 certificate chains be deeper than 3 levels? Is there a ...
11
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3answers
5k 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 ...
11
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2answers
2k 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 ...
11
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2answers
909 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 ...
11
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1answer
811 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
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1answer
503 views

What is going on with my download of the recent Apple security update?

The update in question is the Mavericks combined update which, among other things, claims to fix the recent SSL vulnerability/gaping hole. This issue really annoyed me, so I decided to procure ...
11
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2answers
180 views

Detect Man In The Middle From An Application [on hold]

I did an interesting experiment today. I opened Amazon.com in my browser, logged in, brought up Fiddler, and tried to add a brand new credit card. I typed in my credit card number, expiration, and ...
10
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2answers
5k views

How can I prevent a man-in-the-middle (MITM) attack on my Android app API?

I checked out the app Packet Capture. This app is able to decrypt my app APIs (SSL Enabled) data by mounting a MITM attack using the Android VPN service. This does not even require root. How can I ...
10
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2answers
6k views

How safe is Tor from MITM/snooping attacks?

I am behind an HTTP proxy, and I frequently tunnel out via an ssh -D SOCKS proxy (I have access to a couple of outside servers which I can tunnel to) when the HTTP proxy causes problems1. Now, this ...
10
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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 ...
10
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4answers
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In light of the FREAK TLS vulnerability, why do so many servers still offer RSA-EXPORT keys?

Ars Technica is reporting on a new attack against HTTPS. Called FREAK, the devices reported as vulnerable include iPhones, Android devices, and Macs running OS X. The attack (as has been clarified ...
10
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1answer
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How well is the SSL/TLS handshake protected against modifications?

The SSL/TLS handshake is protected against downgrade attempts by the Finished message, a signed and authenticated hash of the master secret and all previous handshake messages. Consider a client that ...
10
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2answers
8k 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 ...
9
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4answers
2k 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 ...