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### Random data CBC padding scheme?

When using AES in CBC mode, padding is required when the last plaintext block has not the length required by the cipher. Let's say $k$ mode bytes would be required to fill the block. My idea was to ...
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### How Mac-then-encrypt provide security in nonce-misuse setting?

From this, it is clear that Encrypt-then-Mac provides more complete security than Mac-then-Encrypt but some schemes use Mac-then-encrypt to provide nonce-misuse resistance such as SIV (AES-GCM-SIV, ...
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### How secure is Encrypt-And-MAC?

From this popular Crypto.SE thread, the general feeling is that Encrypt-Then-MAC is the most secure. From the first answer, the poster says that Encrypt-And-MAC provides integrity of the plaintext. If ...
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### Is E_k(M)||H(m) form of MAC secure?

Would this encryption and signing scenario be considered tamper-proof? ...
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### MAC-then-encrypt in SIGMA protocol for authenticated key exchange

The SIGMA protocol proposed in 2003 and used in TLS 1.3 and IKE stands for "SIGn-and-MAc" and can optionally protect identity using encryption. The SIGMA-I variant illustrated below ...
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### Is CTR more secure than CBC?

In cryptography, a block cipher mode of operation is an algorithm that uses a block cipher to provide information security such as confidentiality or authenticity. A block cipher by itself is only ...
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### CBC mode works well for input greater than “b” bits. What is that “b” bits?

This post on geeksforgeeks.org about block cipher modes of operation, says that one of the advantages of the CBC is that it works well for input greater than b bits. I also saw that in the book "...
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### authentication by keyed hash function

assume i have: One-key cipher: E. Hash: H My application is authentication. I have a shared secret key with Bob for the One-key cipher. So, when I send an message to Bob, I also send an authentication ...
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### What is the advantage of Encrypt-then-MAC over Encrypt & MAC separately the plaintext [duplicate]

For secrecy, authentication & integrity, you can either use CipherText = Encrypt(PlainText) Signature = Hash(PlainText) CipherText = Encrypt(PlainText) Signature = Hash(CipherText) Either ...
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### Why is MAC encrypted in TLS data transmission? [duplicate]

Referring the slide 16 from this link: I want to ask why is MAC encrypted along with the data to be transmitted. Why isn't MAC just appended at the end of encrypted data ?
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### What is the difference between Symmetric authentication systems and Symmetric encryption systems? [closed]

I know Symmetric encryption systems. Can someone explain the difference
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### During padding oracle attack (CBC), how is first byte of plaintext block is obtained?

Imagine conducting a padding oracle attack against CBC mode with 16-byte length blocks, and PKCS#5 used for padding. You start, as always, revealing the last byte of plaintext. Then you iteratively ...
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### Safely store data before moving to air-gapped machine

This is related to an earlier question, Is it possible to use an algorithm to generate an OTP? I have two machines: A, and B. A is connected to the internet and files are uploaded regularly. B is ...