RSA is a common public key algorithm, which can be used for encryption and signature. It is a core component of most the security protocols used on the Internet, including the SSL/TLS protocol suite.

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Non-identified algorithm for RSA decryption in tpm-emulator

While analyzing the source code of tpm-emulator I found that the RSA key decryption uses an algorithm that is unknown to me. The original file with this mystery is located in rsa.c, where the ...
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How does a chosen ciphertext attack work on textbook RSA?

I am very new to cryptography and I am confused with something. Here is the homework question I am having trouble with: Write a program to attack the Textbook RSA Encryption Scheme, in order to ...
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Does password protected git public key protect my repository?

When generating my public key for GIT access, I decided to set up a password for it. My push procedure looks like this now: Enter passphrase for key '/c/Users/USERNAME/.ssh/id_rsa': Counting objects: ...
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Crypto++ RSA - Encrypt and sign with the same key pair

I have a program A which needs to send messages to several instances of program B (B1, B2, etc...). The messages must be encrypted, and also signed. Which means only Bn instances can decode, and they ...
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RSA 3072 is 65,536 more difficult to factor than 2048? [migrated]

If RSA 3072 is equal to 128 bit symmetric and 2048 is equal to 112 bit symmetric then 128-112= 16 and 2^16= 65,536. In that case wouldn't this make 3072 more future proof against quantum computers or ...
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Why use a passphrase for RSA key?

Today I generated my first key pair, so my knowledge here is - so to speak - very limited. On client side I am using Windows and to log in I use PuTTY and I used PuTTYGen to create the keys. Here ...
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What is the largest cycle of RSA encryption?

Is there a maximum length of a message before it is impractical to use RSA?
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105 views

Why doesn't my manual RSA key exchange example work?

I'm trying to "manually" compute how the premaster_secret is computed using the RSA key exchange in TLS 1.2, but can't manage to make numbers meet. I am using Scapy SSL to generate a TLS session: I ...
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How can I show RSA OAEP IND-CPA secure [migrated]

How can I show, that RSA with OAEP is IND-CPA secure by using G,H one way function?
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137 views

Is this algorithm really end to end encrypted and secure?

I'm creating an anonymous chat where one of the premises is that the conversations are end to end encrypted. I'm using firebase so all the comunication between the clients and the server is SSL ...
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Clarification of RSA Key Exchange (TLS 1.2) and AES for On-Going Message Excahnge

I'm trying to understand the full flow of key exchanges for secure communications. As a potentially incorrect premise, I am under the impression that RSA is a good asymmetric technique for ...
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33 views

JSON Web Token Security RSA

We are planning to use JWT (JSON Web tokens) in an application project, which is a set of multiple distributed web services allowing SSO authentication (single sign on). So there is a single central ...
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Is it ok to use one key pair for my authentication endpoint?

I have an web endpoint that checks user passwords, then issues signed JWT tokens to the client if password matches what we have in the database. The JWT is signed with a RSA private key using RS512. ...
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96 views

Questions on the variations of RSA keys

I've built a simple application that reads in an RSA key, checks the header and starts identifying properties of the RSA key to make sure it is valid (Using child_process in express to run $ ...
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Should RSA primes p and q should differ in length by “a few digits”? [migrated]

When generating RSA keys in the original RSA paper it is stated: "to gain additional protection against sophisticated factoring algorithms, p and q should differ in length by a few digits" Why is ...
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114 views

Is using “SHA-256 with RSA-2048 Encryption” a secure certificate hashing algorithm?

Is using "SHA-256 with RSA-2048 Encryption" a secure certificate hashing algorithm? I don't think it is. Two examples: nsa.gov [careers site] give.wfp.org
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106 views

What is the difference between a digital signature and whole message encryption?

I am newbie in information security I am trying to understand the difference between a digital signature and encryption of a message. Lets consider simple example of email message. I understand how ...
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1answer
191 views

How do I find a PKI smart card reader/writer for development (Microsoft .NET)

I would like to learn how to develop software leveraging PKI smart cards. Ideally, I would use Microsoft Base Smart Card CSP, but I really just need the ability to store symmetric and asymmetric keys ...
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477 views

PKCS#1-1.5 encoding - is there a reason to use 00 in block type?

For encryption block looking like this: EB = 00 || BT || PS || 00 || Data where BT - block type and PS - padding string, I've read that we use three types of BT - 00, 01, 02. Now, since 00 and 01 are ...
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Self-chosen fixed RSA PIN in addition to a Password

I'm using a Junos Pulse Secure Access Service (Juniper Networks), which requires to enter a RSA PIN in addition to the password. I don't know if this is always the case or if it's a custom ...
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27 views

Using the same public exponent for RSA on multiple machines

I have a system where many machines running the same software work independently of each other with no central server of any kind. A user may wish to speak with another user privately and securely, ...
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Is this RSA/AES combination good?

The team of developers I am part of is trying to develop a safe way to exchange sensitive data between a server and mobile devices. We have come up with the following algorithm: Device generates ...
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681 views

Determine private key size using public certificate [duplicate]

I have a public certificate in a PEM (.pem) file -----BEGIN CERTIFICATE----- MIICsjCCAZqgAwIBAgIJAMA1YIQ2JLXDMA0GCSqGSIb3DQEBBQUAMBExDzANBgNV ... 29V/R9RZOoSBHDzGPL84wm4qojMuwQ== ...
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Verify a key was signed by another key

I began using GPG4Win/Kleopatra, the GNU Privacy Guard implementation for Windows. More recently I wanted to verify a download of Qubes OS, for which a guide is offered here. They describe a master ...
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247 views

Are RSA Key Pairs unique?

I generate RSA key pairs mostly using the following command: ssh-keygen -t rsa -b 4096 -C "someemail@hostname.com" which produces a public-private RSA key pair. If I run this command again and ...
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Which part is the longest when gerating RSA key pairs?

Whether I use openssll or gnutls's certtool, I end in a single threaded part which take several minutes. When I try to compile the libraries with auto-parallelizer advanced efficient tools. It sill ...
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New PGP key: RSA/RSA or DSA/Elgamal?

I wanted to create a new PGP key using GPG Keychain Access on my Mac. One of the options was to choose keytype: RSA and RSA DSA and Elgamal RSA (Sign only) DSA (Sign only) I found this Superuser ...
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How much faster does a GPU or FPGA crack an RSA key compared to a CPU?

Are there any significant speed up in time on cracking an RSA key (either brute-force or factoring with general number field sieve) using a GPA or FPGA compared to a CPU? If there is a speed ...
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Someone logged in server through ssh using my RSA key

I just got the warning message from hosting provider that my server make outcoming traffic 1.5G to provide DDOS attack on someone host, and they disabled my VPS temporarily. When I search through ...
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Is it bad that my ed25519 key is so short compared to a RSA key?

I recently generated a new SSH key in the ed25519 format. The public key is only 69 bytes long while my old RSA key is 373 bytes. From my perception ed25519 is the more recent and secure format. So ...
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Why SMIME decryption works with sender and recipient private key?

Im developing an application, that needs to use SMIME encryption and authentication. I've implemented a decryption system, and am currently testing it. I send the emails with another fully working ...
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Is this good/secure method for client-server communication encryption?

Something came to my mind, and I wonder if this is proper method for client-server communication, and if this method is wide-used. On connection, client generates seed, encrypts it using asymmetric ...
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Is webkey a reasonably secure authentication system?

I just created Webkey in the last couple days. It's built to do client-certificate auth without using the (in my opinion unusable) client-cert functionality built into browsers. It would allow ...
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Is the RSA private key useless without the password?

I notice whenever I generate a new gpg key (using pgp) I always have to assign a password to it, which makes perfect sense. But if I'm not mistaken, gpg is based on prime numbers. How is this ...
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Security weaknesses in using RSA encrypted MD5 hash of certificate content

Suppose you have an Internet banking site based on a secure web server running the HTTPS protocol via port 443. The server authenticates itself to clients through an X.509 certificate signed by a ...
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Signature algorithm with ECDH ? can we use RSA or ECDSA ? or ECDSA is compulsory?

I am going through RFC 5656. I want to know if ECDH with RSA is allowed? (I am not SSH ECC compliant).
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Why does this key get Base64 encoded prior to use?

I wish to have my server encrypt messages to clients who have each provided the server with an RSA public key, as well as having the clients authenticate their messages to the server using their ...
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Strange RSA usage - how secure is it?

Is following communication scheme secure? To my mind, it uses RSA modulus and public key exponent as a cryptographic secret, which is strange usage of RSA, but can it be easily broken because of ...
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940 views

Why does the linux XRDP module use a 512 bit RSA key?

Why does the linux XRDP module use a 512 bit RSA key? 512 bit RSA keys are broken by now. How can this be safe?
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Can a device be TLS compliant without RSA?

Let's consider an embedded device which supports ECC and some symmetric cryptographic primitives but not the RSA algorithm. Can it be TLS compliant? I think that if the device and the server share a ...
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RSA rainbow table

Wouldn't it be possible to create as many as possible key pairs for the RSA encryption and then determine from a public key which the corresponding private key is ?
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What would be a simple example of an asymmetric encryption function (asymmetric function)?

I am trying to understand RSA encryption but the algorithm seems quite complex. I know that with asymmetric encryption you use a key and a function to encrypt data and a different function to decrypt ...
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Authenticating a user by verifying a signature

Background I'm setting up an API which will be used primarily over HTTPS (only calls not needing any security what so ever is available over HTTP). Some aspects of it need to be accessed only by ...
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Encryption: Files that can't be encrypted/cryptolocker family doesn't encrypt?

Are there any type of file whatsoever that can -not- be encrypted? Is there any data that can't be encrypted by the regular RSA encryption methods? Also, does anyone know what files the cryptolocker ...
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When should I use symmetric encryption instead of RSA?

I'm currently using GPG RSA keys to encrypt binary files. Many people recommend using symmetric keys to encrypt large files, and then encrypt the symmetric key with a public key. At what file size ...
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GPG/Bitcoin usb gadget device

My idea is to take a raspberry pi zero (or any embedded linux board) and shove GPG inside it to encrypt/decrypt/sign data with RSA/ECC (for bitcoin) via USB. Like a USB thing that holds your ...
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63 views

Minimal working configuration for reasonable security in openssh on Linux [duplicate]

I want to connect from my laptop to home server (both run some Linux; notice I explicitly want my user to be able to become root, in order e.g. to install new software): the server has the following ...
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Will quantum computers render AES obsolete?

This is a spin off from: Use multiple computers for faster brute force Here's at least one source which says that quantum computers are on the way to being able to break RSA in the not too distant ...
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How could an attacker read the content of php session variables?

In my PHP code, I am generating an RSA keypair, sending the public key to the visitor and storing the private key in a session variable. Is it possible that an attacker might somehow be able to read ...
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CSR with only public key with openssl

So I have been doing my research and haven't found anything specific enough to my problem. As the question title states, I want to make a CSR with only the public key. What I have been able to do is ...