Hot answers tagged

16

The HSTS header stops MitM attacks by instructing the browser to always send HTTPS (as opposed to HTTP) request to the domain until the policy expires. So a browser that respects the header would send a request to https://example.com even if the user clicked a link to http://example.com. The logic behind HSTS has not changed since it was defined in an RFC ...


8

SSLStrip worked rewriting https requests to plain http, removing the protection and allowing both eavesdropping and modification. A server with HSTS protection will set a header on a HTTPS request asking the browser to only contact that server using HTTPS: Strict-Transport-Security: max-age=31536000 In this case, for one year the browser will only ...


6

Either you give the public key to Bob when you physically meet him and mutually verify identities (as at a key-signing party), or Bob verifies your public key through a trusted introducer (e.g. a Certification Authority) This is the "Infrastructure" part of PKI.


5

Effectively they can see everything you do that's not encrypted or sent through a tunnel and in many cases they can see what type of traffic that is too via DNS. I'll list a few examples: What sites you frequent. When you're active on-line. What operating systems you use and in many cases what software you use. How often you patch your computer. The ...


4

TL;TR: there is maybe (or maybe not) some substance to the patent but I consider the claims made in the press widely exaggerated. I don't see any substance for the claims of helping against MITM. And it addresses different use cases than TLS, so no need to compare. While there was lots of press end of 2014 about this issue it basically repeats the same ...


4

No, it is not possible to determine the state of SSL pinning at the client. SSL pinning is part of the certificate validation done solely inside the client and the only feedback the server gets is if the validation succeeded (connection continues) or not (connection closed, maybe TLS alert). Also there is nothing fully reliable the server could to to "ask" ...


3

Begin each session by having the client generate a symmetric encryption key, encrypt it with the public key of the server, and send it to the server. Both server and client can then encrypt all further communication during the session with that symmetric key. An impostor server would not have the private key of the server, so it can not decrypt the ...


3

Look at the chain of custody. At the point of origin, you have a client; the client has a computer with a secret document, a ZIP program on it, and a secret password. At the point of receipt, you will accept the ZIP file, decrypt it with the secret password, and process it. We can assume that you and your clients are equally susceptible to attack at the ...


3

There are always risk, the ones you are asking about have more to do with physical access and physical loss of the media. As many others have mentioned encryption is going to play a big part in helping with your solution. I'd recommend taking a step back and looking at the specific risks that concern your business and this data in particular then creating ...


3

In this case, no, your device will not be subject to MITM of https traffic. It is possible for employers to deploy a root certificate to machines in order to install a MITM proxy. (BlueCoat is a company that offers such a device commercially.) However, that requires a "trusted root" certificate to be installed in the client computers. In your case, the ...


3

My question is has the malware installed proxy server on my pc? Based on your description this is very likely. How the malware has done this? Use of proxy is only a registry setting or similar (i.e. browser profile) setting and can be changed by a process (no manual interaction required). How to resolve this issue? Unless you have ...


3

The result of this attack is not really different from someone compromising your router, your ISP, your VPN endpoint or similar: the attacker will be able to intercept and modify the traffic. Depending on the way the attack is done and depending on the characteristics of the line (i.e. FTTH vs. xDSL vs. cable...) one might detect changes to the line ...


2

For sites like google and facebook several browser have preloaded HSTS (enforce HTTPS) and HPKP (certificate/public key pinning) settings. This means that the browser knows that these sites should be reachable by https only and how the certificate should look like. And this means that stripping SSL and the HSTS header (i.e. your --hsts option) will not work ...


2

Here is something interesting from Bruce Schneier's blog: Many wireless keyboards have a security vulnerability that allow someone to hack the computer using the keyboard-computer link. (Technical details here.) An attacker can launch the attack from up to 100 meters away. The attacker is able to take control of the target computer, without ...


2

What is this certificate being used for? A standard implementation of WPA or WPA2 in enterprise environments is to use certificate-based authentication for wireless network access. For company-owned devices, it makes connecting to a company wireless network seamless - the required certificates are automatically installed at some point (during ...


1

As per OpenID Connect Core documentation: The nonce parameter value needs to include per-session state and be unguessable to attackers. One method to achieve this for Web Server Clients is to store a cryptographically random value as an HttpOnly session cookie and use a cryptographic hash of the value as the nonce parameter. In that case, the ...


1

I assume that you are connecting from your personal device. Many companies have their own certificates on their network somewhere in order for them to check HTTPS traffic going through their network. In many countries it is legal for companies to read traffic using their equipment, and they find this necessary to protect against viruses etc. As they can't ...


1

Assuming you have control of the network equipment then yes you can log and monitor their actions. Full packet capture: Ideally you want full-packet capture of all traffic at key ingress/egress points for each segment. You asked for the best way to do this and this would give you the most data about traffic on your network. Even if you can only capture the ...


1

It depends on what you are trying to achieve. If you are trying to prevent DNS leaks, DNSCrypt isn't what you need. DNSCrypt is intended to prevent DNS spoofing, which is quite different. You could think of it as Privacy vs Man-in-the-Middle. DNSCrypt is a protocol that authenticates communications between a DNS client and a DNS resolver. It prevents ...


1

My suggestion is a little different to what you asked: Download the app Packet Capture from the Google Play Store and install it on your Phone. Start the app, skip the generation of the root certificate (or generate one - this will help you decrypt SSL traffic), and start a capture. You can then capture and analyze packets directly on your phone - ...


1

Android requires app updates to be signed by the same key as the original app. So unless the developers themselves have been compromised, a MITM won't be able to update existing apps. Note that this process is completely unrelated to SSL certificates. App signing certificates are self signed and don't rely on certificate authorities for trust. It sounds ...


1

I have a similar set-up, a whitelisted linux ftp server, receiving an encrypted file in the clear, and have asked similar questions. For one, I have it set up as anonymous, since what is the point of a login in the clear? Second, it is whitelisted, so the only theoretical vulnerability is IP spoofing. I read up on IP spoofing specifically in regard to ftp, ...



Only top voted, non community-wiki answers of a minimum length are eligible