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The 1024 bit number on the key describes the modulus used as part of encryption and decryption of a message (see https://security.stackexchange.com/a/8914/29905), which is paired with a public exponent for the public key and a private exponent for the private key - effectively, the message is first taken to the power of the public exponent e or the private ...


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First of all, a 1024-bit RSA key is much too small for comfort. Current recommendations for RSA are a debate between 3072 or 4096 (better security margin) vs. 2048 (better performance). See: https://crypto.stackexchange.com/questions/19655/what-is-the-history-of-recommended-rsa-key-sizes https://paragonie.com/blog/2019/03/definitive-2019-guide-cryptographic-...


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Asymmetric encryption is more useful when communication is with untrusted parties since you can keep the private key safe while sharing the public key more loosely. Symmetric is more useful between trusted parties as the key is needs to be more secure. So if the purpose of the webhook is to integrate a trusted application to post messages to your Slack ...


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From a purely theoretical sense - it is only possible if you can make sure that after the first decrypt there are no copies in existence of both the decrypted data, and either the encrypted data or the key(s) needed to decrypt it. In principle, you can only do this with the cooperation (willing or coerced) of the parties that handle these pieces of ...


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It is not in any way practical, and fundamentally impossible (in a reliable way), but it may be possible to some extent. The obvious hindrance which makes the endeavour fundamentally impossible is that whatever it is you decrypt, once you've read it, it's inside your head. So, to be sure the secret stays secret, there would have to be a poison pill ...


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If a network is available, you could offload the decryption procedure (and the private key) to a service running on a secure server. You could then enforce whatever rules you want on the server. The client would submit the opaque text to the service and ask it to decrypt it and return the plaintext content, and the server could decide whether the client ...


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As you already hinted at, such a thing is only possible in hardware. A software or encrypted data solution would always suffer from the option of making a copy before decryption. In hardware, the scheme would be to destroy information on decryption. A naive approach would be to simply read a block into memory, destroy it on storage and then decrypt it. ...


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My overall goal is to be able to verify the message is valid, and retrieve the message (does not matter if it's visible or not) with the smallest overhead possible, with both endpoints under my control, but the communication is always stateless and easily modified by a third party. You don't seem to require encryption, since it "does not matter if [...


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There is no way to do this - this is a subset of what DRM schemes attempt to do. If an end user can decrypt something once to see it, they can see it again. Any of the following may be possible: first take a copy and decrypt that copy the screen edit the application The only way you could get close would be to have total control over the hardware and ...


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I assume that "the way of sending the CA's certificate to another party" is the process where you sent the CSR to the CA to be signed. What if some hacker is monitoring the network in the moment you send a certificate to other party and hacks the public key from that certificate? He will most likely intercept the encrypted SSL connection. No CA that ...


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Is FeliCa encryption safe? Yes, but also no. Yes, insofar as there doesn't appear to be any published cryptanalysis attacks against the cryptography employed by FeliCa. No, because it isn't an open standard. This makes it difficult for cryptographers from all over the world to review and audit the function. Instead, Sony is relying on a small pool of ...


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For file encryption it does make sense to stream ciphertext or to use a memory map of a file. Buffering the whole file is definitely not the way to do things. If you want to use parallelization then you need to split the file into chunks and encrypt / decrypt separately. That will give you authentication tags (and possibly nonces) for each encrypted chunk ...


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This is really an often overlooked mechanism. The way a digital cert is bound to an identity is by digital signature from a certificate authority. A certificate authority (CA), is an entity which is entitled to sign and 'vouch' for the identity of other entities. They act as a trusted party. Even more interesting is that for this whole system to work, ...


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If you are dealing with text files of size 64 GB or even smaller I believe you should chunk the file and start encrypting portions immediately. This was the former option you mentioned above. The reason to use GCM vs something like CBC is because GCM can be run in parallel while CBC which is equally secure cannot. If you 'waste' the cpu's ability to start ...


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Yes, it's bad practice to use a key for two different purposes. This can have obvious or subtle problems. In this specific case, I don't see an obvious security problem. Rfc2898DeriveBytes implements PBKDF2, which is a key derivation function. Given the output, it's impossible to reconstruct the input except by guessing. Since a private key has enough ...


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There is no security advantage to AES-XTS over AES-CBC-ESSIV—in fact, in the standard threat model for disk encryption (an adversary can read multiple snapshots of a disk, e.g. because of bad sectors on spinning rust or wear-leveling in an SSD), XTS leaks slightly more information than CBC-ESSIV: XTS leaks exactly which blocks in each disk sector didn't ...


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Storage, not communication There's a serious overlap between integrity and authentication in the context of exchanging messages, as the other answers correctly note. However, look at the risks that apply to data in rest (not data in transit) - for a database, the authentication risks (an unauthorised user being able to read and/or write what they should ...


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You are not missing anything. There is no meaningful distinction in cryptography between ‘integrity’ and ‘authentication’ of data on a channel between two parties. Any attempts at distinction in the context of an adversary wallow in confusion of epistemology without a difference. (If you really like the cute acronym CIA for spook stuff, maybe use the A ...


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Example of integrity without authentication You download a file and a corresponding checksum over HTTP, and an attacker intercepts both the file, and the checksum. You compare the checksum of the received file with the expected checksum, and it correctly shows that the file is intact. It shows you received what you were intended to receive, but not that the ...


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Let me correct this. Notice the bold parts, and removed steps 1- During registration: user insert password hashing function generates unique salt hashing function adds the salt to the password hashing function generates a hash from password + salt the hash and the salt are sent to the application database 2- During login: user insert password the ...


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