Non-repudiation is the ability to prevent an identified individual from repudiating a specific action or communication associated with that individual.
Questions tagged [non-repudiation]
43 questions
3
votes
3 answers
Authenticity of PDF document printed from Word
My MS Word Add-In generates PDF preview of DOCX file on client PC and uploads both files to server. I cannot generate PDF on server.
Is there any way to make sure that the PDF is the printed version created by the plugin from the actual DOCX? I need…
![](../../users/profiles/89.webp)
bretik
- 1,840
- 13
- 22
3
votes
2 answers
HMAC and non-repudiation
This was a question on an exam:
Two persons are using a one way communication channel and the HMAC functionality (concretely HMAC-SHA1). Choose the correct statement below:
1) We can prove who the sender is, because HMAC-SHA1 uses a shared secret,…
![](../../users/profiles/61316.webp)
RunoTheDog
- 177
- 1
- 7
3
votes
2 answers
Does Non Repudiation offer proof of receipt ?
I understand that non repudiation intends to provide a mechanism that reliably proves that the sender of a message cannot deny sending the message. But does it also provide similar mechanisms to ensure the recipient of the message cannot deny…
![](../../users/profiles/41816.webp)
user1720897
- 603
- 2
- 10
- 18
3
votes
2 answers
Does SMIME differ from TLS, PGP, DMARC signature, or a Portal Encrypted email message in terms of legal non-repudiation?
I'm interested in protecting email messages from NSA-style snooping, but don't want to incur additional legal risk in doing so.
In other words, does SMIME encryption and/or signing cause a given email message to have more legal "power" than a…
![](../../users/profiles/396.webp)
makerofthings7
- 50,090
- 54
- 250
- 536
3
votes
1 answer
How online document signing services guarantee non-repudiation?
There is a number of services online like RightSignature or SignHub that will let you sign online legally binding documents. I understand how documents can be signed digitally and this can guarantee that they were not altered, but I do not…
![](../../users/profiles/26814.webp)
Dan
- 163
- 4
3
votes
1 answer
How does choosing where a password is stored affect non-repudiation? (or private key storage)
Password managers, and numerous tools have been created to store end-user secrets over the years. This proliferation has resulted in a hazy mix of opportunities to improve security.
In short, I think this could be broken into the following groups.…
![](../../users/profiles/396.webp)
makerofthings7
- 50,090
- 54
- 250
- 536
3
votes
3 answers
Is there a way to prove authorship in a shared repository?
Say, we have a number of people working on some kind of collaborative effort (such as a research paper or a software project) that is committed into a shared repository. However, a certain subset of these people are also conspiring against the rest…
user22260
2
votes
3 answers
How can Alice and Bob prove that they share a file?
Carl asks Alice and Bob if they have a file f such that for a secure cryptographic
hash function h, h(f) = K.
Both claim to have f, but they can't show the file.
Carl doesn't believe them. He can ask further questions to Alice and Bob, although…
![](../../users/profiles/70561.webp)
user70561
- 21
- 2
2
votes
3 answers
Doesn't Authentication logically imply Non-repudiation?
If it is confirmed that Alice is the source of a message (authentication), then shouldn't she be unable to deny that the message is from her (non-repudiation)?
Is there an example where authentication happens without non-repudiation?
![](../../users/profiles/185732.webp)
explorer
- 121
- 3
2
votes
1 answer
Sign a document as created with an authorized software build
I'm creating some software that essentially enforces a specific process for creating specific documents, which protects them from being challenged later.
Afterwards, the file is signed with the user's key (USB token not related to the software).…
![](../../users/profiles/118127.webp)
ZOMVID-21
- 2,450
- 11
- 17
2
votes
1 answer
How to implement a digital signature for 21 CFR Part 11 for non repudiation
I would like to know what is the best way to implement a digital signature to achive Non-Repudation to acomplish 21-CFR-Part11-SubpartC-11.100.part-c. Anybody has implemented this for 21 CFR 11?
Non repudiation means that if a users sign the…
![](../../users/profiles/136518.webp)
Ekaitz Hernandez Troyas
- 121
- 2
2
votes
1 answer
Can I guarantee non-repudiation with this authentication protocol?
I have read that a symmetric key cannot guarantee non-repudiation, but in Mark Stamp's book "Information Security: Principles and practice", he gives this strong mutual authentication protocol:
This protocol uses symmetric key, so my question is:…
![](../../users/profiles/104329.webp)
Luz A
- 31
- 6
2
votes
2 answers
Can CA certificate be spoofed on the browser level?
Can a certificate be spoofed at the browser level?
Meaning I go click the LOCK image in my url bar and it shows a valid certificate from VeriSign but somehow the attacker spoofed that information. I'm not sure how they could do it and that's what…
![](../../users/profiles/132630.webp)
IEnjoyEatingVegetables
- 150
- 7
2
votes
1 answer
what is worth a digital signature based on email address only?
I have noticed that most digital signature providers do not try to certify anything but an e-mail address, while it is quite easy to create an email address without disclosing any personal information.
Thus, I may know the e-mail address of a…
![](../../users/profiles/93196.webp)
Pierre ALBARÈDE
- 121
- 3
1
vote
3 answers
Non-Repudiation that can Never be Proven
I understand that non-repudiation is based upon public key cryptography and the principle of only the sender knowing their own private key. However, what is a condition, if any, of non-repudiation that can never be proven through digital analysis?…
![](../../users/profiles/35369.webp)
larrylampco
- 123
- 5