65
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 ...
4
votes
2answers
96 views

How to troubleshoot “client certificate” related errors in 2 way HTTPS

I have a webserver which is asking for client certificate for mutual authentication. I have what I think is the right certificate loaded into my client browser. However, the browser is not able to ...
5
votes
2answers
123 views

How can I enable opportunistic encryption for my web-site?

As per an honourable mention in an answer for « Why self-signed https is less trustworthy than unencrypted http? », it appears that there are already two post-Snowden drafts that have to ...
3
votes
4answers
255 views

Why self-signed https is less trustworthy than unencrypted http?

It wouldn't be far-fetched to guesstimate that at least 50% of the web traffic can be intercepted in 2014. However, a guesstimate of active interception attacks is likely an order of magnitude ...
-1
votes
1answer
58 views

How does SSL client authentication work?

I read the RFC document, it mentioned that there are some kinds of client certificate type. So I don't understand what does this type mean. For a instance, one type named rsa_fixed_ecdh, it said, the ...
1
vote
0answers
36 views

How to add user entries with password field in LDAP over HTTPS

I am new to this kind of stuff (HTTPS etc.) and pretty much confused on how to go ahead with this. An LDAP server (ApacheDS) at the back-end stores the user details. To add new users, the user ...
1
vote
2answers
86 views

VPN over HTTPs for a web service only

I have a web service (PHP & MySQL on Ubuntu 12.04) running in a corporate intranet. I have also connected it to internet through a firewall letting incoming connections on HTTPs only (port 443). ...
0
votes
1answer
58 views

SSL Mutual authentication Fails

When I try to establish a Mutual authentication between server and client, I am getting the errors below. The timing between the server and client is exactly same and also the certs are proper in ...
3
votes
1answer
87 views

What stops an attacker from tampering with data sent during the SSL/TLS handshake?

On this page, it says the first thing sent is the SSL settings, such as version, and cipher settings. If the attacker, say, wanted to change the encryption method used, what makes this not possible?
0
votes
1answer
53 views

ChangeCipherSpec Authentication

According to RFC 5246, 7.1. Change Cipher Spec Protocol: The ChangeCipherSpec message is sent during the handshake after the security parameters have been agreed upon, but before the verifying ...
5
votes
1answer
619 views

What's keeping a malicious man in the middle server from forging a valid certificate

According to process of authenticating a server certificate: What's keeping a malicious server to fill up a valid server certificate since it knows all the things: Forged Server public key (man ...
4
votes
1answer
148 views

Is it a security risk for users not to logout of a website?

Is it a security risk to myself that I am not logging out of Twitter, Facebook, StackExchange, and a majority of the sites which I am using? Is there a chance for someone to hijack my session or cause ...
2
votes
2answers
52 views

Does HTTP Digest Auth provide any increased security in this scenario?

Say I have a website running a popular CMS like Wordpress only over SSL through HTTP Strict Transport Security. Prior, the backend administrator login page could be accessed by anybody simply by ...
4
votes
2answers
112 views

What's the meaning of the term “ad-hoc MAC” (Message Authentication Code)?

In SSL literature, I've noticed the use of the term "ad-hoc MAC". I understand the meaning of MAC (Message Authentication Code) and how it works, but what does the term Ad-hoc MAC mean? Note: With ...
1
vote
1answer
109 views

SSL Handshake random number?

I realized all of the phase of the handshake but I do not understand how it does that from the two randomly generated numbers are unable to generate a session key that the client and the server uses ...
1
vote
1answer
54 views

Client authentication flaw in old Netscape SSL protocol

Below is a screenshot from the paper "Prudent Engineering Practice for Cryptographic Protocols" by Martin Abadi and Roger Needham. I can't see what's wrong with the protocol and what the fix achieves. ...
1
vote
2answers
158 views

LastPass login security

If LastPass does not store your master password, then how can you login to use their web app? Surely you must type it in, it is sent over using SSL, and then salted/hashed on the server-side, and ...
11
votes
2answers
1k views

Does having 2-factor authentication help with HeartBleed?

I was talking with a friend about HeartBleed, and he mentioned that he had 2-factor authentication enabled on all the sites that supported it, so even with his username and passwords, nobody would be ...
1
vote
2answers
175 views

SSL/TLS : Authentication mechanism

I have these doubts regarding authentication in SSL/TLS : Will there be an authentication involved for all SSL connections ? For eg. when I browse the internet, using the most up-to-date browser, ...
1
vote
1answer
94 views

Is there any way to restrict multiple access to my server at the same time using one client certificate?

My Server is Windows 2008. Mr. X is accessing my web server using Mr. X's certificate. In that time, an outsider is also trying to access my server using Mr. X's certificate (somehow he got it). Is ...
1
vote
1answer
85 views

Use TLS certificate as both server and client?

For a federated server-to-server protocol with domain-based identities, I am thinking of using TLS client certificates as authentication mechanism. I figured that re-using each peer's TLS server ...
1
vote
0answers
92 views

Is my approach to anonymous certificate based HTTP(s) authentication and secure private messaging sound?

I'm trying to work out a somewhat anonymous secure messaging system, and was hoping someone could validate my overall approach. Keep in mind, this all takes place over HTTPS. Authentication While ...
3
votes
1answer
112 views

What are industry-standard recommended practices to protect user information in an Android app?

I am developing an Android app that will potentially handle sensitive user data, and some of it may be even considered medical data (for example user height, weight, alergies, etc). What would be the ...
0
votes
1answer
109 views

Why not use client certificates for premaster key generation

The question is about a very specific SSL handshake scenario. I understand that some servers may request client certificates in order to authenticate connecting clients. However, as far as I can ...
2
votes
2answers
425 views

Should login pages be cacheable?

I'm considering the relative benefits/disadvantages of making a login page cacheable. Note that here I'm referring to the page containing the form into which the user enters their username and ...
2
votes
1answer
150 views

HMAC needed with SSL/AccessToken in place?

Is using an HMAC in web service messages overkill if you are already using SSL and Access Tokens? I’m thinking of further ways to secure a service, and HMAC message signing is one. But it comes with ...
1
vote
1answer
60 views

Transport Layer Security for multiple persons

I know that TLS protocol is used to authenticate two persons and when a secure channel is established we can perform a key exchange. My question is if TLS can be used to establish a secure channel ...
0
votes
1answer
187 views

How does the MITM (Man in the middle) attack happen with respect to SQRL

I recently looked into SQRL and was intrigued by its simplicity. At first glance it seemed reliable and its author claimed it was inherently fail-proof against phishing and MITM attacks. But upon ...
0
votes
2answers
561 views

Client Authentication by certificates in Google APP Engine java

I am writing an application in Google APP Engine java which authenticate the user by its certificate. I have created a self signed certificate using keytool at client side. I also enable the HTTPS ...
2
votes
3answers
148 views

Website Authenticity/Verification without SSL

Are there any other ways of verifying the web server you're visiting is actually the correct one? For example, if a domain name's DNS was hypothetically hijacked, and users were directed to a phishing ...
5
votes
2answers
388 views

Trustworthy Android recovery image that allows rooting?

I have an unlocked but not rooted Android device (Nexus 7 2013 WiFi "flo", legitimately unlocked using fastboot oem unlock from an x86 computer). Neither adb root nor adb shell followed by su let me ...
0
votes
1answer
135 views

Can I use a CDN for static content without sacrificing SSL keys?

I would like to use a CDN for the static content of a website. But obviously I do not wish to share my SSL key with any external service. What are my options? An ideal solution would be to link to ...
0
votes
2answers
102 views

SSL/TLS Question [closed]

I am currently working on my SSL/TLS assignment and I got a question to ask. What is the use of a login password since it is not needed for establishing secret communication between your computer and ...
1
vote
0answers
299 views

Safe communication via rest api between two known servers

i would like to have some advice on the following scenario: I'm using kinvey as backend but because it doesn't provide the ability to run custom code i have set up another server. So basically when x ...
5
votes
2answers
279 views

Can I trust large companies like Google not to store failed password attempts?

Let's say, for example, that I accidentally entered my Microsoft account password instead of my Google account password when logging in to some Google web service. After getting an error message, I ...
7
votes
3answers
2k views

Is HTTPS and Basic Authentication secure enough for banking webservices (RESTful)?

I have been reading about SSL/TLS for the last few days and looks like it has never been practically cracked. Given SSL/TLS is used for all communications between client application and the server, ...
4
votes
3answers
2k views

Safe to expose Active Directory via LDAPS externally?

We currently access Active Directory via LDAPS internally for authentication and user data retrieval. Is it common, or safe, to expose this publicly over LDAPs? Addendum 1: Our business case, ...
1
vote
1answer
446 views

Additional security for WebRTC/DTLS-SRTP with PGP?

I am having a thought experiment. Can you help me? Two clients who both use PGP. They initiate a WebRTC call using DTLS-SRTP via a 3rd party server. Is there any benefit of encrypting, via their ...
0
votes
2answers
495 views

mutual authentication between two clients

I understand how mutual authentication works between a client and a server, however I am unsure how I would be able to get mutual authentication between two clients A and B? What would be the best ...
1
vote
1answer
86 views

Certificate Mapping in IIS

When pasting the certificate blob in the configuration editor in IIS 7.5 for one on one authentication, is this the server certificate or the client certificate?
2
votes
1answer
219 views

Communicate between two sites both with SSL

I now have two websites - site A and B, both with SSL-certificate, and they have exact same users. So when a user log into site A and click the link to site B, I want to make him auto log in to site ...
4
votes
2answers
625 views

Website: Pre-Shared-Key Authentication

We have this web-application with high valuable (business) data. All communication is encrypted through TLS/SSL. While I consider this a really safe protocol, it can still be compromised if someone ...
4
votes
2answers
313 views

Login security without SSL

I have a web app without SSL (I know it's not good, I try to take it as a challenge). The login is two step. First the admin sshs into the server and runs a maintenance companion program that provides ...
4
votes
2answers
161 views

Can the client certificate authentication process treated as a user digitally signed the content(and then get verified on the server)?

The authentication was triggered by certain event (like approving button) on the form. In the process of client certificate authentication (in IIS), user was asked to use their PIN (private key) and ...
1
vote
1answer
439 views

Transparently authenticating users or devices on mobile devices

I have an interest in using EAP-TLS to authenticate both users and devices separately on mobile devices (phones, iPods, tablets, etc.). My issue is how to delineate between user authentication and ...
2
votes
2answers
484 views

A protocol to authenticate users without login/password

A casual message exchange on reddit yesterday got me thinking whether it might be possible to design a protocol that removes the need for users to remember a unique password for every service (s)he ...
2
votes
2answers
173 views

SSL/TLS Client Authentication by IP

Is there any mechanism in SSL/TLS which allows a certificate to be bound to a device? Example: There is a client who talks to a server, and during SSL/TLS setup, there is mutual authentication. ...
1
vote
1answer
650 views

Why can I see the Basic Auth credentials in plaintext when using SSL

I just read this about the security about Basic Authentication over SSL: Is BASIC-Auth secure if done over HTTPS? And I don't get it. I just installed ProxyDroid (http proxy) on my rooted android ...
8
votes
1answer
387 views

Build a secure channel without SSL/TLS

I'm looking at possible options to build a secure channel between multiple embedded devices with limited cryptography capabilities and an HTTP server (It could be some sort of web service). 1. ...
12
votes
3answers
1k views

Multi-tenancy, SSL Certificates, and Subject Alternative Name

The X509 specification allows a CA to issue a single certificate for multiple hostnames, by using the "Subject Alternative Name" extension. From the spec: The subject alternative name ...