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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Why is there a “des-ede3-cbc” in my rsa private key?

I have created an OpenSSL RSA private key and certificate request with 4096 bit with the following command: openssl req -newkey 4096 When I view the private key with openssl asn1parse -in privkey ...
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1answer
32 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
48 views

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

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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38 views

How do I decrypt a RSA-SHA1 code? [on hold]

I am working on one project where I am having a RSA-SHA1 modulus code and Exponent value only. which is as follows: Modulus: ...
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1answer
25 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
28 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) ...
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20 views

Do all attacks against PKCS1 v1.5 encryption require an oracle [migrated]

As far as I know, all attacks against RSA PKCS1 v1.5 require an oracle; is that true? Or are there any other attacks against it which are able to break it without an oracle? Background: I need to ...
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2answers
33 views

HPKP and multiple SSL certificates

Some weeks ago, we enabled the HTTP Public Key Pinning header on our website. As per the specification, we included not only the SHA-256 fingerprint of our current RSA key, but also that of a backup ...
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28 views

Good Library for RSA-2048 in C with some restrictions [closed]

I'm looking for a C/C++ implementation of RSA with a 2048 bit key (preferably read from a file). My target is an embedded platform, so it comes with some odd restrictions. The hardware restricts us ...
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12 views

Risk to pgp secret keys with known cleartext/ciphertext? [duplicate]

There are a couple of schemes which encrypt IMAP message stores to yourself using GPG/PGP. Which makes initial sense and would keep casual snoopers from getting email. But it raises a question as ...
2
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2answers
159 views

Chrome status warning on a netbanking secure site connection [duplicate]

I visited my bank's web banking site and clicked on the Green Lock in the address bar of my Google Chrome browser out of curiosity. Under the "Connections" tab Chrome spits out this disturbing ...
2
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2answers
229 views

Encrypting USB traffic: Is RSA necessary for AES session key exchange when using pre-installed secret keys?

I need a solution to encrypt USB communication between device A and device B. I was thinking about configuring each device with a secret RSA-2048 key, which would be used to exchange an AES-256 ...
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1answer
2k views

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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2answers
84 views

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 ...
2
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1answer
164 views

Can i know how 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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1answer
38 views

Passing data among 3 parties with public key encryption

There are three parties involved in a repeated data transfer process: Client C, Broker B and Provider P. There might be multiple clients C. Broker B manages P's customer database. Each customer has a ...
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2answers
368 views

Converting ECC Private key to PKCS#1 format

Is there any way to convert an ECC private key to RSA PKCS#1 format? I have tried converting it to PKCS#8 first using OpenSSL: openssl pkcs8 -topk8 -nocrypt -in EC_key.pem -out pkcs8_key.pem This ...
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1answer
66 views

RSA/ECB/PKCS1Padding: Encypting a Session Key Javascript

How to do ECB mode when dealing with RSA? I dont understand it. The Aadhar authentication doc (http://uidai.gov.in/images/FrontPageUpdates/aadhaar_authentication_api_1_6.pdf Page 33) says that we have ...
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2answers
55 views

FREAK attack - why doesn't Finished message prevent it?

Here is my understanding of FREAK (let me know if I'm right please): 1) Client wants to use modern RSA in ClientHello 2) MITM forwards Export_RSA 3) Server says ok and sends an export RSA key, ...
4
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1answer
97 views

Why did browsers deprecate 1024-bit RSA, but retain SHA-1?

I was reading Mozilla's security blog Phasing out Certificates with 1024-bit RSA Keys. Effectively, some browsers are deprecating 1024-bit RSA for CAs and Subordinate CAs because the certificate must ...
3
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1answer
107 views

toy OpenPGP encryption with manually generated keys

I've been playing around with OpenPGP encryption for a little while. Here are the steps I've followed: Generate an unencrypted public/private key pair in my keyring with gpg --gen-key. Dump the ...
2
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1answer
63 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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2answers
86 views

Encryption / Decryption algorithm generic across JRE (Sun/IBM)

Is there any encryption algorithm that is generic across all platforms? Is RSA generic across SUN/IBM JRE? Another question: will base64Encoder / base64Decoder sun.misc.BASE64Decode / ...
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1answer
44 views

How ECDHE is signed by RSA in ECDHE_RSA cipher

About ciphers that use ECDHE as Key Exchange and RSA as Authentication: How exactly this two algorithms work together, is ECDHE process encrypted by RSA public key? What are the DH parameters? ...
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2answers
168 views

RSA public key and private key lengths

I'm having a problem understanding the size of an RSA public key and its private key pair. I saw different key sizes for RSA algorithm (512, 1024,... for example), but is this the length of public ...
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2answers
77 views

Secret, Public, and Private Keys?

...and nonces. Can someone show an example of how this actually works using small intelligible numbers? For example: secret key: "100" public key: "10" private key: "1000" I am just trying to ...
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4answers
560 views

What is the role of RSA in ECDHE-RSA? [duplicate]

I have read some textbooks and not found a convincing explanation. In the cipher suite ECDHE-RSA-AES128-GCM-SHA256, what is the role of RSA in the first part (ECDHE-RSA)? This part of the cipher ...
2
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1answer
201 views

SSH Key: Ed25519 vs RSA

A lot of people recommend using Ed25519 instead of RSA keys for SSH. The introduction page of Ed25519 (http://ed25519.cr.yp.to/) says: [..] breaking it has similar difficulty to breaking [..] RSA ...
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3answers
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Key size difference between AES and RSA

Can I say that 128 bit using AES provide more security than 1024 using RSA?
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1answer
48 views

Who uses 1024-bit RSA?

I know they're deprecated, but does anyone still use 1024 bit RSA encryption or certificates? Do you know of any examples of systems that use it today? What would be the implication if someone ...
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1answer
87 views

Managing keys generated with insufficient entropy

Since the Linux RNG which provides /dev/random (and by extension /dev/urandom) is seeded by "mouse and keyboard activity, disk I/O operations, and specific interrupts" (source, PDF) and since virtual ...
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62 views

Choose your own exponents in RSA?

In another interesting post, one of the developers/security researchers behind Phuctor suggests that using different exponents with RSA keys will "[increase] the costs of attacking your setup ...
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60 views

Offline RSA strong prime test similar to Phuctor?

One of the ways that RSA keys get consistently owned is when they're generated without enough entropy. Dan Kaminsky refers to a study which found that 1 in 200 RSA keys were badly generated and these ...
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1answer
57 views

Prevent padding oracle attack on key exchange process

I found in my searches that the padding oracle attack can be used against the RSA with PKCS1PAdding or OAEP padding, and I used this algorithm for a symmetric key exchange. How can I prevent a padding ...
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1answer
63 views

RSA: same symbols in plaintext give same symbols ciphertext?

I just started studying Information Security, but I just ran this program: http://www.sanfoundry.com/cpp-program-implement-rsa-algorithm/ and faced this strange thing. For small keys (don't try to ...
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1answer
83 views

What is encryption by RSA with AES? [duplicate]

By visiting some websites, like bank websites, we can see for example: TLS_DHE_RSA_WITH_AES_128_CBS_SHA, 128 bits, TLS 1.0 I would like to know: What does mean CBC? TLS 1.0 is an old version, is ...
3
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1answer
1k views

openssl ECDHE-RSA… cipher suite selected while using RSA server cert and ECDSA client cert

The scene: s_server using RSA certificate. s_client using ECC-ECDSA certificate. Client authentication is required (option -Verify set on s_server) Cipher-suite selected after handshake is ...
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3answers
145 views

Secure Hash of a very short payload - is it possible?

I am looking to verify the integrity of a very small payload, approx 64 bytes, which will be stored in a QR code. I need to verify that the payload has not been generated or altered by an attacker. ...
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1answer
56 views

Determine private key size using public certificate [duplicate]

I have a public certificate in a PEM (.pem) file -----BEGIN CERTIFICATE----- MIICsjCCAZqgAwIBAgIJAMA1YIQ2JLXDMA0GCSqGSIb3DQEBBQUAMBExDzANBgNV ... 29V/R9RZOoSBHDzGPL84wm4qojMuwQ== ...
5
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1answer
171 views

How many qubits are needed to factor 2048-bit RSA keys on a quantum computer?

I've been reading about quantum computing and turns out that 512-bit quantum processors are already a thing. I also read about Shor's algorithm, which can break RSA and several asymmetric encryption ...
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1answer
56 views

RSA vs DSA Digital Signature Message Digest Recovery

I'm learning about signatures using RSA and DSA, I've come across this little fact: RSA can recover the message digest from the signature, whereas in DSA this isn’t possible – you have to have the ...
2
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1answer
109 views

someone may be doing something nasty

I have an ssh server. earlier toady, I was about to login to my server, when I got a message that said something along the lines of "Someone may be trying to do something nasty" and indicating a man ...
3
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1answer
8k views

Create RSA public, private key pair having numbers generated already

I want to know to to generate working RSA key pair, with correct syntax. Let's say i have already generated somehow my numbers for 512bit key, which are: e = 00065537 d = ...
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1answer
495 views

Share and store RSA - public key in java server and vice versa

My requirements are: Requirement 1: Share public key to java server. Steps: Generate public-private keys in iOS app. Store the generated keys in keychain. Send generated public key to java server. ...
2
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1answer
111 views

How does this encrypted webmails works?

In the last days I was looking on Tutanota, ProtonMail, LavaBoom, and others webmails that promise to respect users privacy. For all those, the one I most liked was Tutanota. I did few tests with ...
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3answers
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If TLS 1.2 is considered unbreakable, why do the NSA and other agencies invest in supercomputers? [closed]

If a 2048-bit RSA key and a 256-bit AES key are considered to be unbreakable within the foreseeable future by any kind of computer, why do the NSA and other intelligence agencies invest in ...
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123 views

Encrypting short data with RSA only?

I have a case where I need to create recovery accounts and I want to create them so that nobody knows the password to them until/unless necessary. Hence, I thought that I would do it using RSA - when ...
2
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0answers
51 views

How to use IIS ssl certificate(CNG) for data encryption

I want to use RSA to encrypt/decrypt some data using IIS's ssl ceritifcate, from within a web service(WCF). I've managed so far to do this by using .NET security ...
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1answer
78 views

RSA private/public keys

Is it possible to recover a private key, given a public key and a substring/a part of the corresponding private key?
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1answer
82 views

RSA vs DSA working methodolgy?

I have looked for various answers but I am being confused on how does RSA can be used for both Digital Signatures and Encryption/Decryption like in "TLS_DHE_RSA_..." or "TLS_RSA_.." cipher suite ...