Questions tagged [diffie-hellman]
The Diffie–Hellman key agreement is an anonymous, non-authenticated key-agreement protocol.
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Diffie Hellman Pre Master Secret too long
As far as I understood, when using Diffie Hellman, the pre master secret is generated as follows:
Alice and Bob agree on a generator g and a prime p
Alice chooses a primary key a, calculates A = g^a ...
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What will be the key size for rsa, ecdhe and ecdsa from the cipher suite given?
From the cipher suites tls_rsa_with_aes_128_cbc_sha256 and tls_ecdhe_ecdsa_with_aes_128_cbc_sha256 how do I know what will be the RSA , ECDHE, and ECDSA key support in IBM cloud Watson?
here is the ...
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ECDSA ECDH Man In The Middle Attack
We have a long-term key used for signing/verifying the ephemeral keys. The problem is we have to first share the long term public key with the other party. Is it possible to avoid a man in the middle ...
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WPA technical doubts (3)
This is the third post about the set of doubts that came up when I tried to understand WPA3. I am new to this world of cyber-security so every bit of help is welcome!
Someone told me that in WPA2 ...
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Is this a correct DH key exchange over RSA wirelessly?
Note: I am a network researcher, but a security newbie. Hence, this post may contain wrong understanding of security including DH and RSA. If it does, please let me know it.
I've designed a certain ...
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SSH wireshark trace and Diffie-Hellman G and P parameters
I have a problem spotting both "DH base (G)" and "DH modulus (P)" in my sshv2 trace. I scrutinized each message exchanged between both my ssh client and the ssh server, there is no trace of "DH base (...
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Clarification on DH groups
Nikto reports the following via the "ssl-dh-params" NSE script:
Check results:
| WEAK DH GROUP 1
| Cipher Suite: TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
| Modulus Type: Safe ...
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End-To-End encrypted calls over GSM transport (not data / VoIP)
As the issue stands, it should be (or could be) possible, to encrypt voice, that's being passed through GSM voice call in such way, so that it's end-to-end encrypted.
Ideally in form similar to what ...
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Can Fido2 hardware tokens be used for key agreement or Diffie-Hellman?
With Fido2 becoming more popular we see more and more affordable Fido2 hardware security keys on the market.
Can we use those tokens also for establishing a shared secret between two tokens?
I would ...
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Diffie Hellman with server public key embedded on the client
First, I realize trying to come up with your own crypto schemes is not a good idea. I'm a relatively new member of a team of developers utilizing such a custom scheme and I'm trying to come up with ...
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Understand DHE security in TLS
SSL Labs says that a website I control supports weak ciphersuites because they have DH 1024 bit, e.g. this one: TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 (0x9f).
I tried to connect to the website from my ...
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Advantage Of ECDH-RSA over RSA Ciphersuites In TLS
If ECDH-RSA is used for key exchange, this is what happens:
The server has its public ECDH parameter embedded within its certificate. The client generates its public ECDH parameter, extracts the ...
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How to perform a MITM attack on SSH exploiting the Diffie Hellman key exchange
I have an open-ended project for a class and I picked to make a tool/use existing tools and applications to exploit the Diffie-Hellman key exchange to be able to inject, modify and delete messages ...
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Is ECDH easier than DH to be broken?
As I am a security newbie, this post might have lots of misconceptions about security. If so, please let me know
I've heard that ECDH is preferable to DH because its smaller key size and lower ...
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How to verify the usage of dhaparameters configuration from command-line?
Although Qualys will happily do it for Internet-reachable systems, some of ours are on private networks. I'd like to be able to verify them all remotely.
Is there a "quick" recipe -- something based ...
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How to generate DSA keypair for browserID
As a bit of a learning exercise, I'm trying to understand and implement a client for the Firefox Accounts Browser sync API.
I'm up to the point where I'm trying to ask the server to give me a ...
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Any Suggestion Exchanging shared key between process via port in untrusted machine (infected my malware)?
I am trying to get shared key between Firefox extension and a java program running in same machine. I am communicating both application via socket.
My assumption is that malware is running in ...
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Evading authenticated diffie hellman with MITM
I understand that in a non-authenticated Diffie-Hellman setup, a man-in-the-middle attack can occur. Now i'm curious about the feasibility of the following scenario:
Let's assume a situation where www....
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IIS Crypto 3.2 not getting rid of Diffie-Hellman algorithms of less than 2048-bits
I'm trying to stop a server using Diffie Hellman key exchanges of less than 2048 bits, but I'm getting confusing results.
I've run
Get-TlsCipherSuite | Format-Table Name, Exchange, Cipher, Hash, ...
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Question about Diffie-Hellman key exchange
It is known that a man-in-the-middle attack on the Diffie-Hellman key exchange protocol in which the adversary generates two public-private key pairs for the attack. Could the same attack be ...
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ESP32: Secure WiFi credentials via WebCrypto?
Background information:
I am not a computer scientist. However, in a research project I am currently building a ESP32-based sensor. Multiple sensors of this type are going to be used by multiple users....
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symmetric key generation in TLS 1.3
Am trying to understand the phase where the symmetric key is getting generating. From what I am understanding Diffie-Hellman is used to derive the symmetric key in TLS1.3
I am reading this tls ...
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Can a secure key-exchange algorithm replace hashing for password authentication?
Over the weekend I was thinking about the problem of scaling various web services. One common practice to scale authorization is to use cryptographically signed tokens. This way when a request comes ...
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how to encrypt and decrypt messages with more than one sender and more than one receiver?
I am creating a chat app. This app contains private messages and channels. These channels include more than one user.
I want to encrypt messages using AES and to transfer the AES key to users of this ...
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how to send prime and generator of diffie hell-men to client over network node js?
I am using crypto module of node js for exchanging key using diffie-hellman algorithm.
server.js
const crypto = require("crypto");
const alice = crypto.createDiffieHellman(512);
const aliceKey = ...
