Questions tagged [replay-attack]

Attacks that are based on recording an encrypted and/or signed communication and replaying it at a later time.

Filter by
Sorted by
Tagged with
0 votes
0 answers
47 views

How to use nonces to prevent replay attacks while enabling concurrent requests?

Nonces are often used to prevent replay attacks in networks. Because they are a one time use, any attacker replaying a request would be stopped because the nonce would be invalid. However using nonces ...
user avatar
1 vote
1 answer
52 views

Can a nonce be completely random on (simplified) Needham–Schroeder Protocol?

From what I've read so far, nonces are random one-time values, which are sent in plaintext in addition to the ciphertext to verify identity of sender/receiver. Theoretically, if the nonce is random, ...
user avatar
1 vote
1 answer
47 views

How to properly guarantee authentication, confidentiality, and replay-resistance for multiple messages using a pre-shared key?

I have a device that needs to communicate with another host and exchange fixed-length messages. All traffic should be encrypted and authenticated, and it should be resistant to replay attacks. ...
user avatar
  • 111
2 votes
2 answers
654 views

Is it OK to use r-value from ECDSA signature (r, s) to prevent replay attack?

ECDSA signatures are malleable. Given a valid signature (r, s), one can create a second valid signature by negating the s value. I have searched workaround for this issue, and https://yondon.blog/2019/...
user avatar
3 votes
1 answer
70 views

Replay attacks and LWE

Just a small question. Since in LWE the error is rather small, is there a problem with replay attacks? What I mean is that if we use the typical scheme of Regev [1] to encrypt a vector m, but this ...
user avatar
1 vote
1 answer
74 views

Could PAKE via smooth projective hash function protect agaist replay attacks?

I came across some password-based authenticated key exchange (PAKE) protocols that are based on the smooth projective hash function (SPHF) in the standard model. And I checked some related works, and ...
user avatar
  • 333
1 vote
1 answer
52 views

If two hosts are using a transparent IP level authentication and encryption, is their communication subject to both MITM or replay attacks?

Encryption process for any outgoing packet to the specified "remote IP": -original payload P is encrypted (the bytes after the IP header) using RC4 with the preestablished key ...
user avatar
  • 13
1 vote
1 answer
790 views

Replay attack resistant MAC?

I came up with a threat model where: Alice and Bob agree on a shared key $K$ Alice sends a plain text $M$ and its $\operatorname{MAC}$ tag, $T = \operatorname{MAC}(K,M)$ to Bob over an untrusted ...
user avatar
  • 113
0 votes
1 answer
260 views

What's the utility of the last two messages of Needham Schroeder Symmetric key protocol

The protocol works like this But I can't understand what's the utility of message 4 and 5, what do they protect from? They do not protect from replay attack if Ks gets compromised because B won't be ...
user avatar
0 votes
1 answer
135 views

Random oracle : Replay

What I understand about the random oracle game: The adversary can query the oracle polynomial many times with the same (secret but unknown) key. From the output returned by the oracle, the ...
user avatar
  • 593
2 votes
0 answers
61 views

No freshness protection for single messages, but for the overall protocol

I am given a key exchange protocol between a component $C$ and a key master $K$. During the overall execution 4 messages are transferred between $C$ and $K$. DH keypairs are always chosen randomly for ...
user avatar
1 vote
1 answer
450 views

AES-CCM replay attack and nonce

My wireless sensor nodes and gateway application use timestamps as nonces and guarantee that different messages use different nonces so that security is not compromised. If the gateway does not ...
user avatar
0 votes
1 answer
219 views

Entity authentication protocol by encryption

I'm not a cryptography expert, so excuse me if the question seems very trivial. I need to know if this protocol is secure against a MiTM attacks and ensure a safe entity authentication method. We ...
user avatar
3 votes
1 answer
1k views

Timestamps, sequence numbers, and nonces for replay attack

What are the best practices or standardized methods to prevent replay attacks in a simple server client setup (preferably where the server is stateless) ? When should timestamps, sequence numbers, ...
user avatar
1 vote
2 answers
136 views

What is the connection between "replay attack" to CCA security?

Often in analyzing systems, the emulation of Replay Attack becomes important. Are systems that protected against CCA attacks also immune against replay attack, or it is a different criterion? Thanks
user avatar
2 votes
1 answer
1k views

Getting a Keeloq manufacturer key

I have seen a lot of articles and research papers about breaking the Keeloq algorithm. My understanding is that the hardest part is getting the 64 bit manufacturer key. Some methods use crypto-...
user avatar
1 vote
1 answer
414 views

How to detect if a protocol is vulnerable to a replay attack trying to impersonate?

I'm having a hard to finding out how I can detect if protocols are vulnerable to impersonation of Alice/Bob by Eves' replay attack! I have an example here: $$\begin{array}{lclcl} \mathsf A & \to &...
user avatar
1 vote
1 answer
2k views

AES-GCM Encryption and Replay Attacks

I have a doubt about AES-GCM on how can I avoid replay attacks. We have 2 users (Alice and Bob). After that the entities negotiate crypto parameters and generate a symmetric key, they'll exchange ...
user avatar
  • 361
2 votes
2 answers
1k views

Can One-time-password be used as nonce in HMAC to prevent replay?

Note: In the following post OTP = one-time-password I am working on a project wherein I need send one way messages between two end points. There is already a shared secret via a side channel between ...
user avatar
  • 163
1 vote
2 answers
484 views

How to stop an attacker from repeating the same ciphertext?

I have this situation where a PC is connected, via RS-232, to a certain hardware module that controls industial machinery. The hardware is supposed to receive commands to turn on or off these ...
user avatar
  • 115
0 votes
1 answer
474 views

About replay attack definition

I have read . Replay attack is a kind of attack in that the attacker eavesdrops valid message and sends that message repeatedly to make requestor in busy mode. It can be prevented by adding timestamp ...
user avatar
  • 313
8 votes
1 answer
341 views

Is a key ratchet effective against replay attacks?

In the answer to this question, a message counter is used to protect against replay attacks. Could a key ratchet be used instead? The basic idea is that with every message sent, the symmetric ...
user avatar
  • 203
3 votes
1 answer
548 views

Why is a nonce used to initialize Hash_DRBG, HMAC_DRBG, and CTR_DRBG?

In NIST 800-90A, Hash_DRBG, HMAC_DRBG and CTR_DRBG (with derivation function) all require a nonce for instantiation. I understand the usual application for a nonce to prevent replay attacks. However,...
user avatar
8 votes
1 answer
2k views

Replay attack prevention in connectionless UDP encrypted communication

What are the options for replay attack prevention when two parties exchange UDP messages. No connection or session is estabilished. Communicating parties have pre shared key that is used for ...
user avatar
  • 183
2 votes
1 answer
541 views

Very simple and minimal replay prevention scheme

Suppose a desktop client communicates with an internet server program via HTTP requests. I have a symmetric secret key shared between them used for encrypting/securing communication between them. I ...
user avatar
  • 447
9 votes
1 answer
4k views

Can I use a HMAC for Replay Attack protection?

I am considering a system where a small device accepts messages/commands from another device over a wireless channel. I am worried about replay attacks. The messages will be encrypted. What are ...
user avatar
  • 185
3 votes
3 answers
5k views

Prevent replay attack without storage

I am designing a set of low-power sensing motes. Each mote will communicate to a central base over RF. I want the mote to be able to authenticate itself with the base, and send its data without being ...
user avatar
  • 33
3 votes
1 answer
234 views

Avoiding replay attack on certified announcements

Suppose two agents A and B share a common secret and A makes a regular unique 16-byte ...
user avatar
  • 463
1 vote
1 answer
732 views

On countermeasures for replay attacks. Does this one require plaint text password storage?

I was reading this wiki section on the countermeasures against replay attacks and it basically suggests that: If Bob wants to confirm Alice's identity he can send a one-time token (I think it should ...
user avatar
  • 113
1 vote
1 answer
685 views

Replay Attack in Stream Cipher

Stream ciphers are vulnerable to replay attack if the same key k is used. If E() is a stream cipher and an attacker intercepts the message m that's being transmitted at time t, how can the attacker ...
user avatar
  • 113
1 vote
2 answers
1k views

RSA signing security

I'm curious about the security of RSA signing with the same public private key pair when the same message is sent multiple times. It's my understanding that once you generate the hash of the message ...
user avatar
0 votes
1 answer
893 views

What happens when cbc+hmac get a replay attack?

If it use AES-CBC and HMAC-SHA256 for message send online, and someone try to replay attack on this message. Can the attack be successful? what will be happen when attacking?
user avatar
2 votes
0 answers
189 views

Does the initial exchange of random tokens in SKID3 authentication assure against replay attacks?

As the question suggests, I wanted to get a sanity-check on this issue... is it the case that the use of a random token exchange during SKID3 authentication itself constitute a prevention of a replay ...
user avatar
  • 21
21 votes
3 answers
39k views

How does a rolling code work?

I have general questions regarding rolling codes. Basically there is a sender and a receiver. Both have a sequence generator. The receiver checks if the received sequence matches the newly generated. ...
user avatar
1 vote
1 answer
673 views

Which of the following protocols is susceptible to replay attack?

I have a hard time understandin which of the following protocols is susceptible to replay attack: A -----> B username, password A -----> B username, h(timestamp,password) A -----> B username ...
user avatar
  • 243
3 votes
2 answers
521 views

Please punch holes in this authentication scheme

Folks, I am undertaking a crypto course in Uni. Our professor asked us to try and design some authentication schemes which are resistant to active attacks. This was just a in class exercise to get us ...
user avatar
  • 245
3 votes
1 answer
2k views

Advantages/disadvantages of different message numbering schemes

For a stream of packets, where each packet is individually encrypted with a block cipher, it's desirable to have each encrypted packet only valid for that position in the stream. A message number ...
user avatar
  • 793
2 votes
0 answers
143 views

Prevent/minimize replay attacks in public message board

Assume we have a public message board where anyone can send a message to. If plain messages are used, anyone can impersonate anyone. The goal is to disallow impersonations. We can use public key ...
user avatar
  • 121
5 votes
1 answer
799 views

Why doesn't this replay attack work on ECDSA?

I've just started working with elliptic curves and ECSDA in particular, so my understanding of the underlying math isn't great. The thing I'm currently stuck on is trying to understand why replay ...
user avatar
2 votes
0 answers
134 views

Computer appliance protocol [closed]

I build the computer appliance system that consist of software server and multiple controllers. The system I want to build must be pluggable in the sense that when I connect a controller C to the ...
user avatar
  • 151
4 votes
0 answers
492 views

How can Alice and Bob safeguard their message exchanges against replay attacks?

Assume Alice and Bob communicate over an insecure channel using one-time perfectly-secret encryption together with one-time secure message authentication code. Say Eve has the ability to eavesdrop and ...
user avatar
  • 129
6 votes
2 answers
7k views

Replay attack in ECB mode

How do replay attacks work in ECB mode? I found this in Wikipedia: "ECB mode can also make protocols without integrity protection even more susceptible to replay attacks, since each block gets ...
user avatar
  • 1,597
2 votes
1 answer
2k views

Replay attack prevention under strict conditions

Say I have a request-response protocol and the task to make it immune to replay attacks. The requirements are as follows: The defense mechanism cannot rely on the clocks of the parties. The defense ...
user avatar
  • 1,172
2 votes
1 answer
5k views

Secure way to transfer data over NFC?

I am currently writing a payment system to accept payment details from an NFC enabled smartphone (BlackBerry 9900) to a Windows client (C#.NET) I am currently having two issues relating to security: ...
user avatar
  • 121
6 votes
3 answers
4k views

How can I prevent a message replay with RSA?

I am using RSA to encrypt some data but I would like to eliminate the possibility of message replay. By message replay I mean sending a valid message multiple times to the original recipient. It is ...
user avatar
  • 1,172