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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On the Import Client Key screen in Bitvise what is numeric field just next to the Location Profile dropdown?

What is this field for? I know I saved a profile in the beginning, and I want this private key to be attached to just the profile that I'm using, but what on earth is that numeric field for?
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38 views

Is D parameter of the RSA strong enough to be used as secret for HMAC calculation?

Short question: Is the D parameter of the RSA alghorithm crypthographically strong enough to be used as a secret key for generating SHA-256 hash value? Long question: I'm working on windows platform. ...
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58 views

What effect would removal of RSA tokens from mobile phone have on surveillance? [closed]

Reading the comments at Bruce Schneier's blog, I came across this recommendation by someone where they write: @Michael_H - Here you go, buy yourself a cheap Huawei G6620 on eBay, any network, ...
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30 views

Storing user private key paraphrase during session

We have a web application which is used to store secrets (passwords, pins etc) and share them to other system users. Currently for encryption we use AES with single encryption key, and all secrets ...
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86 views

secret key not available for decryption, but still shows up in GUI

I'm trying to decrypt a message using my personal secret key. When I try to decrypt the message (using gpg --decrypt message.txt), I get the following error: gpg: encrypted with RSA key, ID 3810D17A ...
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Why is key exchange necessary at all?

Let's say "Alice" and "Bob" want to communicate with each other over an insecure network. Using Diffie–Hellman key exchange, they can get the same symmetric key at last. However, as I understand, ...
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263 views

Using a stolen certificate on a server

Yesterday I asked the following question regarding what would happen if you placed a stolen certificate on your own server and edited the 'host' file so that the DNS name matched: Could a stolen ...
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56 views

RSA and Psuedorandom Number Generator

I want to give a presentation on school about RSA encryption and decryption. I understand the basic of calculating a public and private key with two small prime numbers. And how to use those keys to ...
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2answers
121 views

RSA: Do private keys have to be private?

I was thinking about using RSA, but in reverse. Where everyone has the private key, and only the server has the public key, so that all the clients can decrypt a message from the server, and the only ...
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51 views

How to decrypt RSA cipher text? [closed]

How can I decrypt an RSA cipher text in which I am only provided with a public key and the cipher text. The person who encrypted it made a mistake in taking the exponent.
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103 views

RSA fingerprint automatic change or have I been hacked?

today I tried to connect to my Digital Ocean VPS through Putty(kitty) as usual, but I got the message that the server's cached fingerprint had changed, and that it could be a security compromise. I ...
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Could RSA be used as a block cipher?

I always thought that the reason we couldn't use it was because it required too many CPU cycle. But an answer from @TomLeek indicated that this was not the case : ...
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101 views

Generate RSA2 key in OpenSSH format in windows

I have to generate a key, RSA v2 in OpenSSH format. I am a bit confused. I am trying to generate it using Putty key generator. There I see an option SSH2-RSA and SSH1-RSA. So is SSH2-RSA the RSA2 key ...
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2answers
92 views

Is it possible to protect a DER private key with a password?

I want to write an API, based on OpenSSL, that can convert an RSA private key stored as DER to the PEM format. I'm just wondering if a DER key can be password-protected. I've searched the OpenSSL ...
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1answer
228 views

How can I use my HSM to turn a CSR into a certificate?

I create a CSR using OpenSSL, so I have public and private keys. Now I want to sign this CSR and convert it into an X.509 certificate. The only problem is, my signer is a custom HSM. I can send bytes ...
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1answer
69 views

Public-key encryption for pre-shared keys with MAC

What well-known algorithms are suited for the following task? I need system A (and only system A) to be able to encrypt some data, with system B being able to decrypt it. At system B, I want to be ...
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1answer
68 views

Need asymmetric encryption(not signing) where server encrypts and client decrypts

So I'm trying to build a licensing server, where the licenses of the applications need to be checked when logging in or when the application gets used. But some of those application work offline most ...
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1answer
26 views

Publish an image to github with rsa keypairs, what are the security risks? (NOT PRODUCTION)

I have Dockerfile for an image that I would like to publish to docker hub so it can be easily available to users without building the image themselves. The whole thing is meant for labbing and ...
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1answer
521 views

GPG (PGP) decryption speed issue

We are new to using GPG and we have a very strange issue with decryption speed when using RSA keypairs, which are generated by using different tools (GPG for Windows, DidiSoft OpenPGP Library for .NET ...
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1answer
183 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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2k views

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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1answer
126 views

Encryption and Signature with same RSA private key

Talking about cipher-suites that use RSA both for sign of DH parameters and for digital signature. The keys used for these process are the same, or is there a public and private key for each one? If ...
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3answers
175 views

How to deliver an encrypted message to multiple recipients without revealing keys

Let's say I have generated a private and a public key. I create a message and encrypt it with the public key. I deliver this encrypted message and a private key to multiple recipients. Why would I do ...
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1answer
69 views

RSA signature on TLS

In a TLS handshake using ECDHE-RSA, the ServerKeyExchange frame must include the ECDHE ServerPublicKey, signed with its RSA private key, as specified in the RFC 4492. Got it. Trying to implement an ...
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527 views

Is it safe to use same key pair to encrypt and sign? [duplicate]

Would it be easier to hack a private key by having multiple encrypted and/or signed messages from the same person than having only encrypted or only signed messages? Should I use one private key to ...
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91 views

Public Key Pinning and subdomains

Shortly I have intend to install new webserver and I'd like to secure users a little bit more. I already have domain, (virtual) server and everything else that matters when configuring a server. ...
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192 views

DSA, ECDSA and RSA [duplicate]

Conventional wisdom these days is that in the context of SSH keys, DSA is insecure and RSA is preferred (or that they are both fine, but RSA is more secure, depending on who you ask). As I understand ...
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1answer
374 views

breaking down RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING

So Java has a mode called RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING. What does that even mean? RFC3447, Public-Key Cryptography Standards (PKCS) #1: RSA Cryptography Specifications Version 2.1, section ...
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159 views

Significance of the difference between DSA and RSA in signature verifying speed

I have run openssl speed and the output on my CPU for longest available DSA key size, which is 2048 bits: sign verify sign/s verify/s rsa 2048 bits 0.029185s ...
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369 views

Diffie-Hellman and MIM attack, and server identity

Diffie-Hellman and MIM attack: When variants of Diffie-Hellman algorithms like DHE, ECDHE etc. are used in SSL handshake for key exchange then can it become prone to man in middle (MIM) attack. ...
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302 views

How to unwrap exported key from safenet HSM? [closed]

I am trying to write a software that will inject keys generated inside an HSM into a POS device, in the same way as described here I'm using the Safenet emulator(software-mode) + the wrap/unwrap ...
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1answer
249 views

Using ECC for PGP-Master Key in combination with Yubikey

I acquired a Yubikey Neo last month. Now I want to use the Smart-Card functionality for PGP. I followed the official guides on the Yubico Website tested it with 2048 RSA Keys and it worked fine. But ...
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Is RSA useless when my app is fully decompiled?

I've programmed an Android game with Unity Engine. As you know in Unity, scripts compiled into one file named "Assembly-CSharp.dll". I wrote my scripts in C#. After I compiled whole game into .apk, I ...
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1answer
195 views

GnuPG - Problems with large RSA keys

I have read that GnuPG limits the size of RSA keys to 4096-bits because this could lead to problems with running out of secure memory. But in which operation is this the case? Generating the keys? ...
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1answer
98 views

SSL key decryption [duplicate]

I am wondering if I can get the SSL Key given the following conditions: Encrypted Text is known Decrypted Text is known Any ideas on how I can create a program that does this?
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207 views

ECC and RSA 10K stronger claim

There are a lot of websites where it is claimed something akin to this but no explanation on the basis. "ECC key size of 256 bits is equivalent to a 3072-bit RSA key and 10,000 times stronger than a ...
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1answer
214 views

Use RSA Encryption With ASP.NET

My goal is to implement asymmetric encryption in an ASP.NET website to secure user-entered Social Security Numbers. I want to encrypt the SSNs with a public key, and only display a masked version, to ...
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1answer
402 views

Using RSA for Web Application Authentication

I have a network that is only accessible through bastion servers over ssh. In it, I am developing web applications that are exposed to end users via GUI's served up over websockets. All traffic into ...
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1answer
156 views

How bad an idea is intentionally using short RSA keys for signing CloudFront private-content URLs?

While pondering a question on SO about efficiently generating signed private-content URLs for CloudFront I decided to check what sorts of savings could be found by using a shorter RSA key. With the ...
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1answer
174 views

I need to transfer user's private key (RSA) to my App. Is file sharing a good solution?

I've asked a similar question here earlier iOS: Is it ok to store a RSA private key (use to decrypt text) in your application document directory? However, the person recommend me to use keychain ...
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3answers
329 views

When generating a 4096 bit RSA key pair, do both the private and the public key always have exactly 4096 bits?

When generating a 4096 bit RSA key pair, do both the private and the public key always have exactly 4096 bits, thus do not start with a 0 in binary representation?
4
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1answer
332 views

Sending Encrypted Messages with Hybrid RSA, AES and HMAC SHA-256

Is this a Secure strategy for sending a large Encrypted Message using Hybrid RSA 2048, AES 256 and authenticated with HMAC SHA-256: Given the Alice already has Bob's RSA Public Key, Alice: ...
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2answers
175 views

Using Different Algorithms in Single PKI

Assume the following Public Key Infrastructure: |Root CA (RSA) |-Sub CA (RSA) |-Sub CA (ECC) Is there any rational that explains why this would not be an acceptable implementation? Is the ...
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5answers
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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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2answers
202 views

Why can I sign but not encrypt?

-edit- After following a chain of links from this question I see this is similar/duplicate of Why should one not use the same asymmetric key for encryption as they do for signing? but this question ...
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Is there a pre-established method for cracking RSA SecureID codes?

I am using the most modern version of RSA SecureID's tokens with a RSA server (used with a lot of governments and larger organizations ). I was just wondering if there was a pre-established method for ...
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214 views

What's RSA and ECC's role in TLS 1.2? [duplicate]

I'm trying to figure out what is RSA and ECC used for in TLS 1.2 cipher suites. Let's take TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 for example, communication between server and client would look ...
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1answer
688 views

How to prepare FATCA data transmission files with open source tools [closed]

Here is the context: to transmit FATCA data to US IRS service the IDES protocol defines the following steps sign the XML Payload.xml file with enveloping signature, SHA-256 with RSA private key, as ...
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98 views

Why FATCA IDES “protocol” does not use RSA encrytion directly on Zip archive ?

Here is the context: to transmit FATCA data to US IRS service the IDES protocol defines the following steps sign the XML Payload.xml file with enveloping signature, SHA-256 with RSA private key, as ...
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1answer
108 views

What's the signature structure in TLS server key exchange message?

I'm writing a TLS server. While handling ECDHE-RSA cipher suite, the server key exchange is needed. According to Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS) ...