Linked Questions

7 votes
4 answers
3k views

Is encrypted e-mail sent over TLS 1.3 a form of "forward secrecy" (similar to something like Signal)?

One common complaint about GPG-encrypted e-mail is that it doesn't provide forward secrecy; however with opportunistic TLS becoming increasingly common in both IMAP and SMTP, it's not unreasonable to ...
philomathic_life's user avatar
7 votes
2 answers
14k views

TLS 1.2 is still secure or should we move to TLS 1.3?

There are some vulnerability such POODLE, that allows the attacker to gain access to encrypted blocks of data and then gain exposure to plain text information using side channels. Another ...
R1w's user avatar
  • 1,960
4 votes
1 answer
2k views

How do I multiply two points on an elliptic curve?

Tell me if there is a way to multiply two points on an elliptic curve? For example, as in secp256k1 ...
Derick Swodnick's user avatar
3 votes
2 answers
1k views

TLS 1.3 Security against PKCS#1v1.5

This paper explains an attack on TLS 1.3. This was published way back in 2015 when TLS RFC was in draft stage. My question is now TLS 1.3 RFC is finalized, is this attack got addressed?
Chits's user avatar
  • 115
2 votes
2 answers
575 views

Diffie-Hellman key exchange, then so what?

I know how the Diffie-Hellman Key Exchange (DHKE) works. But where is it used? And ok, now both have the same key. But how are those keys used anyway? I've heard that HTTPS is using the DHKE. Ok, but ...
Kuroi Ryū's user avatar
2 votes
1 answer
508 views

Why is there no "ephemeral non-DH EC" key exchange in TLS?

In RSA key exchange, the client picks a premaster secret and encrypts it with the RSA public key in the server certificate, and sends it to the server. This offers no forward secrecy. In ECDHE key ...
heinzelotto's user avatar
1 vote
1 answer
501 views

Can Fixed–Diffie–Hellman be attacked?

Recently I'm studying Diffie-Hellman key exchange protocol and I've noticed that the basic Diffie-Hellman can be attacked by Man-In-The-Middle attack. I've also read about the Fixed Diffie-Hellman ...
Benny's user avatar
  • 113
3 votes
1 answer
464 views

Can a 3rd party decrypt static Diffie Hellman?

Do cipher suites that use static Diffie Hellman (not Ephemeral) allow for the same 3rd party decryption ability as RSA cipher suites? With RSA key exchange, 3rd parties can gain possession of the ...
Neal Eastwood's user avatar
2 votes
1 answer
152 views

Questions about Symmetric Encryption part of TLS

In TLS, we use DHKE for establishing the session key & then encrypt the actual communication with session key using symmetric encryption. While reading about DHKE, I learnt that you could use the ...
user93353's user avatar
  • 2,245
1 vote
1 answer
162 views

Key generation for DH key exchange - benefits of using KMI

Context We need to generate a key pair in order to perform DH key exchange with the other party. Some suggest to use a KMI solution (think: AWS KMS or like) in order to generate the key pair. ...
user avatar
1 vote
1 answer
88 views

DHE parameters: which parameters need to be random each time?

In DH key exchange, first, both parties need to agree on a generator $g$ and prime $p$. After that each party computes its key (party A: $g^a \bmod p$) and (party B: $g^b \bmod p$), then they exchange ...
user9371654's user avatar