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…
Nikole
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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…
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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…
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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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Is there any cryptography-based assured data deletion technique currently as a standard?

I've recently read part of a book exploring secure data deletion techniques for many storage mediums. In particular, I read about assured data deletion techniques developed for data outsourced to the cloud. Many of the alternatives are based on…
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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…
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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…
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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…
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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…
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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…
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Have any Hybrid Encryption Schemes been defined for Quantum Resistant algorithms?

Now that several quantum-resistant asymmetric algorithms are in the process of being standardized (or indeed are already standardized), and Google has integrated the recently standardized ML-KEM algorithm into their BoringSSL library (which I…
hunter
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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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