Linked Questions
45 questions linked to/from Has AES-128 been fully broken?
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how to break AES [duplicate]
why is breaking a (asymmetric) 1024 bit RSA key less difficult than breaking a 128 bit (symmetric) AES key? Breaking RSA key involves finding the prime factors of a large number. What is involved in ...
31
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Is 128-bit security still considered strong in 2020, within the context of both ECC Asym & Sym ciphers
Given that much of our ECC crypto primitives provide “only” 128-bit security when defined over a 256-bit curve due to pollard-rho, is it then still safe in 2020 to consider 128-bit security safe for ...
40
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Is AES-256 a post-quantum secure cipher or not?
We know Grover's algorithm speedup brute-force attacks two times faster in block ciphers (e.g brute-forcing 128-bit keys take $2^{64}$ operations, not $2^{128}$).
That explains why we are using 256-...
41
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Is AES-128 quantum safe?
I've been reading lately some contradicting messages with regards to the quantum-safe resistance of AES128. First, there are blog posts by Ericsson people like these ones:
Can quantum attackers break ...
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Does Grover's algorithm really threaten symmetric security proofs?
By Shannon's theorem of perfect security, if I give you a ciphertext 'LOUPL', you can do a brute-force attack and then you would find plaintexts like 'HELLO', 'APPLE', 'SPOON', but you can't ...
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For Symmetric Cryptography, why is it considered more important to safeguard a key than the function/algorithm for encrypting/decrypting a message?
As stated for the question above here's an analogy:
You are a robber looking for a house to rob with two different scenarios that might occur.
1. You have a key that you know belongs to a house and ...
15
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How reassuring is 64-bit (in)security?
In Feb 2017, CWI and Google announced SHAttered hash collision attack on SHA1, which took $2^{63.1}$ work estimated 6500 CPU years, to achieve. Therefore, 64-bit should be considered now an insecurity....
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What are the rules for using AES-GCM correctly?
When using AES-GCM I know that I am supposed to use a new initialization vector every time I call the AES-GCM algorithm with the same key. What are other rules must be followed to use AES-GCM ...
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Security levels in NIST Post-quantum project: e.g. AES-128 vs SHA-256
In an article about NIST Post-quantum Standardization project I read about the security criteria of the proposed schemes and there was this table (Level I lowest security, level V highest):
Level I: ...
9
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What is a multi-target attack?
What exactly is a multi-target attack? How does the attack work on different cryptographic schemes (block ciphers, hash functions, elliptic curves)? How can it be avoided?
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Good layperson analogy for password and encryption keys
NOTE: QUESTION UPDATED. SEE BOTTOM OF THIS POST.
I'm writing something where I need to make someone come across as though they know cryptography. I don't know enough, but as cryptography plays only a ...
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Why does NIST want 112-bit security from 128-bit key size for lightweight cryptography?
In NIST's Submission Requirements and Evaluation Criteria for the Lightweight Cryptography Standardization Process document it is stated that:
3.1 AEAD (Authenticated Encryption with Associated Data) ...
6
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1
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Why GCM operation mode with AES-128 is recomended and can we use AES-192 and AES-256 with GCM?
It happens that on the internet I often find that AES encryption should use a 128-bit key only if it is used in conjunction with the GCM mode of operation.
Why only with 128-bit keys?
What happens ...
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3
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When is a cipher considered broken?
We've all read how some people claim AES is broken because there was supposedly a way to get the plain text from a cipher text faster than brute-force. But is this the definition?
Is a cipher broken ...
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Is Mega.nz encryption vulnerable to brute force cracking by quantum computers?
I am interested in Mega.nz cloud storage.
It is using end-to-end encryption.
It says that it uses AES-128 to encrypt files
And there are more details in their white paper
But I saw that quantum ...