A digital signature (not to be confused with a digital certificate) is an electronic signature that is used to authenticate the identity of a message sender or document signer, and usually to ensure that the original message/document content is unchanged (document integrity).

learn more… | top users | synonyms (1)

1
vote
1answer
22 views

How to create a ring signature?

While reading the Off-the-Record-Messaging paper by Nikita Borisov, Ian Goldberg and Eric Brewer, I came across the idea for "ring signatures" which allow a member of a group to sign a message in the ...
1
vote
1answer
50 views

What issues exist in generating a signed, paper-based PGP message stored by a hostile organisation?

I have recently been the victim of having my medical record tampered with by the organisation holding it. Under state law I have a legal right to submit information to be included in my medical record,...
0
votes
1answer
20 views

In what order are digital certificates verified?

I understand how digital signatures work and how they are verified, but in what order does the CA verify each of the attributes of the digital certificate such as version, issuer, validity etc..? Any ...
0
votes
1answer
132 views

Algorithms for transaction authentication

It's unclear to me how transaction signing and transaction authentication work. Industrial solutions use both symmetric and asymmetric algorithms to compute the signature. What does RSA add the ...
-2
votes
1answer
140 views

What scenarios really benefit from signed JWTs?

UPDATE: I have concluded my research on this problem and posted a lengthy blog entry explaining my findings: The Unspoken Vulnerability of JWTs. I explain how the big push to use JWTs for local ...
3
votes
0answers
14 views

How can I improve and secure automated signing?

Automated signing of files, such as software packages or file backups, is inherently risky if a certain level of trust is given to it. Having signing be an automated process means that there's no user ...
3
votes
0answers
60 views

Can I do an enveloping XAdES signature on binary content?

I need to sign some binary content (scanned documents) with a digital signature compliant with European norms, CAdES - XAdES. One option would be to use this library to do a XAdES signature. Is there ...
3
votes
0answers
78 views

How does a Sign tool work?

My basic understanding of how a sign tool works is: Load the zip-file (may be exe, jar, ddl, apk, etc.) which has to be signed to its memory (cache memory of the sign tool). Verify it and unzip the ...
2
votes
0answers
15 views

Signtool validation fails when signing and validating are done in different machines

I am signing an exe from a machine using a cer file. Then when I validate the EXE using the signtool.exe from the same machine, it succeeds. But when I try to validate it using the same .cer installed ...
2
votes
0answers
45 views

Algorithm to generate (and verify) string of 4 quad alpha numeric code

I am writing a system, for which I need to generate unique transaction numbers (which can be verified by myself). I want to use something similar to that used by credit cards, where a string of the ...
2
votes
0answers
37 views

Out of band signature application for banking transactions

I work on a banking signature project. Signing transactions must be carried out on another application to respect the mechanism "Out Of Band". When the user makes a transaction, he must pass to a ...
2
votes
0answers
146 views

How can I sign an rpm package using a smart card?

I have a smart card (not OpenPGP card), and I am preparing to sign an rpm using this card. After signing, I will get two files: my.rpm.sig, and my_id.cer. How can I sign my rpm using these extra ...
2
votes
0answers
131 views

CMS/PKCS#7: specifying signatureAlgorithm with digest?

I'm confused about algorithm selection for Cryptographic Message Syntax (a.k.a. CMS, PKCS#7) signed objects (RFC5652 Section 5.1). The SignerInfo structure (RFC5652 Section 5.3) has two separate ...
1
vote
0answers
50 views

Create a signed file from the detached signature and the clear text file content

Assuming I have the following: data.txt data.ps7 (the detached signature) Can I generate the bundled signed file ? Any example would be great, using C#, Java or openssl or any other tool ?
1
vote
0answers
126 views

CMS signed data OpenSSL verification error

I have a CMS signed data that is successfully verified through Java BouncyCastle library. When trying to verify through OpenSSL, I am getting the following error: >openssl smime -verify -inform ...
1
vote
0answers
138 views

What is the point of signature file in signed JAR/ZIP files

The way JAR signatures (or ZIP for Android) are designed is that they have a manifest file, containing digest for each file in the archive. Then there is a "signature file" that contains digest of ...
1
vote
0answers
227 views

PKCS#7 signed data structure in signed PDF document

Is it mandatory to include PKCS#7 data (OID 1.2.840.113549.1.7.1) octet string into the sequence of PKCS#7 signed data? I mean if you want to sign PDF, you are basically adding PKCS#7 container ...
1
vote
0answers
122 views

Verifying the owner of a signing key

I'm using elliptic curve cryptography (curve25519 and ed25519) for key exchange and signing. The signing and key exchange keypairs are independent. I need two users to be able to verify each other's ...
1
vote
0answers
316 views

Digital signature based authentication schema using two passwords

I'm working on an authentication system for a web based Bitcoin-related service. As part of the service, users do some less sensitive operations (mostly reading and sending various types of ...
1
vote
0answers
63 views

Is the digital declaration just an obscure proposal?

One professor from my university proposed me and some colleagues to work on a paper about the digital declaration (which is supposed to be better than the digital signature) for passing the subject. ...
1
vote
0answers
121 views

Techniques for web-user communication across an untrusted server

I'm designing a web-based notification framework (i.e. a user can subscribe to updates from a service or another user) where communication between users is encrypted. User-to-user communication on ...
0
votes
0answers
8 views

How does XAdES-X-L compare to RFC4998 Evidence Record Syntax

This SE question describes a scenario I don't fully understand the use case or how 4998 can help correct the issue. How and when should XAdES-X-L be used, and where should RFC4998 be used?
0
votes
0answers
17 views

Reuse key to encrypt signed content

I am developing an application which generates JWT tokens which are signed using HMAC-SHA256 algorithm during their generation and later on encrypted using Fernet library. Since the signing and the ...
0
votes
0answers
15 views

GPG4Win - How to read/unsign .txt file to see a proper text message after signing only file

I sign a file of sha 256 checksum of one file for test. I choose only sign options with OpenPGP certificate only...This textfile looking like this: ...
0
votes
0answers
88 views

eIDAS - list of certified qualified electronic signature creation devices

In eIDAS there is written in Article 31: On the basis of the information received, the Commission shall establish, publish and maintain a list of certified qualified electronic signature ...
0
votes
0answers
15 views

Digital Signature on a Passive RFID tag with small-ish memory constraints

I'm pretty new to the crypto and security worlds and I'm looking for some guidance. Briefly, my project involves Widgets (physical items that need to be authenticated) and Gadgets (physical machines ...
0
votes
0answers
34 views

Altering assembly without affecting digital signature

I have discovered a software crack where the license check assembly (.NET) has been altered but the digital signature and the strong name are both still perfectly intact. Strong naming is easy to ...
0
votes
0answers
19 views

Digital Signature - PKCS#7 Response

I have a long xml-style string which looks like this: MIILhMIILhAY......H9WH9W Task given to me is to digitally sign a pdf document. Is there a tool (like jdk keytool or openssl etc) which I can use ...
0
votes
0answers
64 views

Few questions about verifying a DLL signature?

i have few questions about verifying a file's certificate. The use case is as follows: i have a DLL file that contains a resource i need. I'm signing the file with a code-signing certificate, and ...
0
votes
0answers
27 views

Secure transfer with proxy person in the middle

I am new to cryptography, so I would like some validation. I have an unusual use case that I haven't found described anywhere and would like to get some help validating my approach. Alice needs ...
0
votes
0answers
53 views

Digitally signing a digital signature

When might it make sense to digitally sign a digital signature?
0
votes
0answers
60 views

DSS digital signing approach

Under the DSS approach to digital signing, what is the advantage of using two pairs of keys for each signature?
0
votes
0answers
38 views

Smartcard authentification: encrypt/decrypt or ECDSA?

I'm implementing a simple door access control with smart keyfobs. At the moment I send a 32 byte message to the keyfob which it signs with ECDSA and I verify the authenticity with the public key. ...
0
votes
0answers
49 views

deceptive digital signature?

I am new to cyphering and I try to understand this case : my government sends me so-called "digitally signed" PDFs, as you can see below (text only, after "Thanks"). Although there is a certificate ...
0
votes
0answers
238 views

Guidance on Login using Digital Signature DSC (PKCS12 and x509 certificate)

I'm interesting in exploring possibility to authenticate user using their Digital Certificate. The methodology is to first register the DSC from the user and keep their Public key along with Serial ...
0
votes
0answers
498 views

Application Privilege Control in Kaspersky blocks program with no digital signature

I made a small application that displays hello world to the console output and attempted to open it in another computer that had Kaspersky fully updated. When I ran the application, Kaspersky gave a ...