Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [hybrid-encryption]

Hybrid encryption combines secret-key and public-key cryptography into an encryption scheme.

Hybrid encryption keeps the distinctive advantage of public-key cryptography that the sender needs no prior shared secret with the recipient, only her/his public key. And performance is typically better than with pure public-key encryption, in term of speed and size overhead, especially for large messages.

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Multi-party encryption algorithm

To give some foreground information: I acknowledge that I am a cryptography newb and not by any means an expert (and probably never will be). In a recent CS class we had several assignments writing and implementing RSA and Diffie-Hellman. It was fun…
Niko
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Can I replace DH by a post-quantum key exchange in IBAKE for post-quantum identity-based authenticated key exchange?

IETF RFC 6539 IBAKE - Identity Based Authenticated Key Exchange describes a Hybrid key exchange using both Identity based cryptography and a standard ephemeral elliptic curve Diffie-Hellman key exchange. Since that protocol already is a hybrid could…
Andrea Russo
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How to securely map messages to points on an elliptic curve

I'm implementing a demonstration hybrid cryptosystem in Python (FinCrypt, I know the name is bad) and I'm migrating over from my Weierstrass curve implementation, which was based off of this, to one based on Edward's curves from here. However, I'm…
ThePlasmaRailgun
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Why is hybrid encryption more effective than other encryption scheme?

Currently I am learning about Hybrid Encryption but I was not able to find any good study material. Below is my understanding: One of the reason why we use Hybrid Encryption because public-key cryptosystems often rely on complicated mathematical…
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Symmetric encryption using RSA for random generated password

I'm fairly new to encryption, so I wanted to check the logic for a .net solution I'm working on that encrypts data between two parties. the receiving (decrypting) party will have an RSA key pair stored. They will transmit the public key to the…
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What is this called: encrypt $X$ with key $E$, decrypt $X$ with key $D$?

I am a software developer interested in developing an application with cryptography. I can explain what I want to accomplish, but I do not know the technical terms for the cryptographic functions I am seeking. Many Google searches have not helped…
Joe Gayetty
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RSA hybrid decryption via PKCS#11 - unwrap or decrypt?

I have an application that does RSA hybrid encryption/decryption – i.e., messages are encrypted with a fresh AES key, which is then itself encrypted with RSA-OAEP and sent with the message. Decryption then does the reverse. I want to now provide…
Neil Madden
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Using HKDF to derive symmetric keys from a hybrid public-key encryption scheme

RFC 5869 describes HMAC-based Extract-and-Expand Key Derivation Function (HKDF). In section 4, entitled "Applications of HKDF", it states that one of the intended uses is: derivation of symmetric keys from a hybrid public-key…
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Doing RSA-KEM with RSA-OAEP

I am fiddling around with the JS Web Crypto API and creating a hybrid encryption system that uses a symmetric key to encrypt form data with AES256-CBC and and a public/private key-pair to wrap/encapsulate the symmetric key using RSA-OAEP. Currently…
HenningCash
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Is a signature scheme using a hash considered a hybrid cryptosystem?

In Wikipedia there is a page on hybrid cryptosystems. However, although cryptography contains a lot more than just encryption, only hybrid encryption using key encapsulation and data encapsulation is discussed. So my simple question is: should I…
Maarten Bodewes
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What is the "correct" way to authenticate hybrid encryption?

In hybrid encryption we use an asymmetric encryption scheme and the recipients public key to encrypt a symmetric encryption key $K$. I will denote the resulting ciphertext $C_A$. We then use a symmetric encryption scheme to encrypt a message $M$. I…
Guut Boy
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What's bad about idea of public-key/one-time-pad hybrid cryptosystem?

As i know, generally nowadays hybrid protocols are more widely used than either symmetric or public key cryptosystems separately. I read that public key system is used to exchange and share secret via insecure channel so that the key is then used in…
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How can Whatsapp identify forwarded attachments

Sometimes Whatsapp shows that an attachment was often forwarded. How do they know this if the message is end-to-end encrypted? Even with hybrid encryption I encrypt with my key and store my attachment on the server. So do they hash the attachment in…
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Is there a term for cryptographic attacks where you can verify decryption without assuming any known structure on the plaintext?

The questions https://security.stackexchange.com/questions/1696/if-someone-breaks-encryption-how-do-they-know-theyre-successful and https://security.stackexchange.com/questions/119887/how-to-know-if-a-file-is-decrypted-or-not on Information Security…
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Is Googles Envelope Encryption the same as Hybrid Encryption?

Google is advertising the use of Envelope Encryption in their products with their KMS. By the description, it sounds very much like Hybrid Encryption. But since I could not find any reference to Hybrid Encryption, I wonder if there might be a…
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