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
45 views

Is it possible to give legal value to signed web services?

The context is using digitally signed webservices (with XML-DSIG for example) for e-government interoperability between databases. The idea is to give endorsement to both the data publisher and 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 ...
4
votes
2answers
249 views

Certificate Chain - intermediate and root certificate - installed required?

Recently I bought a SSL cert from comodo for my domain - orakoha.com After submitting the CSR etc, domain control verification etc, I am issued with a zip file containing 4 document which I believe ...
3
votes
2answers
235 views

Is signing android apk file with SHA1 digest secure enough?

Google command line example for signing apk files: $ jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore my-release-key.keystore my_application.apk alias_name source: http://developer....
1
vote
2answers
83 views

understanding client certificate - pfx on the general

Today I am given a pfx and told to access a website. I have absolutely no idea what was given to me initially, so please kindly confirm my understanding on a general level 1) the pfx is a container ...
2
votes
1answer
33 views

Does it matter how information is represented prior to signing?

I have messages that will form a permanent record and be stored for a long time. I care about integrity, authentication, and non-repudiation, so I intend to have the clients creating those messages ...
0
votes
2answers
41 views

Files related/required to a digital certificate

I am new to digital certification and I am trying to understand it as well as get my domain certified. I know this question may be broad, but can someone give me a general idea of the usage of the ...
2
votes
1answer
54 views

Signing web forum messages

I maintain web forum software, which is accessible via NNTP and e-mail (as mailing lists). Since NNTP by design allows anyone to spoof their e-mail address, message signing can be used instead to ...
4
votes
1answer
28 views

Best practice: Should I revoke an identity self-signed using SHA1?

When I first created by PGP keypair, my identity was unfortunatly self-signed using SHA1. I later signed again using SHA512. Does it make sense to revoke the SHA1 signature now or will that just ...
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 ...
3
votes
2answers
78 views

GnuPG does not verify signature while decrypting

I have signed file 1.txt, result file is 1.txt.asc. I changed content in file 1.txt.asc (signed content, not signature). Then I verify signature in 1.txt.asc and I get information that signature is ...
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 ...
5
votes
3answers
454 views

Are documents truly “signed” by DocuSign?

I've never been happy with the explanation DocuSign gives for themselves in their own marketing material (e.g. https://www.docusign.com/how-it-works/electronic-signature/digital-signature/digital-...
6
votes
2answers
867 views

How does an attack on a digital signature work?

In our IT Security class we have been told that you need CA's to prevent attacks on a digital signature. Sadly, our docent didn't elaborate how such attack would be performed - I can only guess that ...
1
vote
3answers
181 views

Authenticating user in same sub-domain using cookies

We have few in production websites say site1.dom1.com , site2.dom1.com , site3.dom1.com which are just replicas working on different server. Now we want to extend some application on another server ...
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?
1
vote
1answer
64 views

Is it possible to digitally sign an email twice?

User A encrypts an email with the public key of user B and digitally signs it. User B receives this message and decrypts it. B wants to forward it to user C, encrypts it with C's public key and signs ...
6
votes
3answers
1k views

Verifying android application integrity from server side

I have android applications (Mobile banking) that connect to my server and do online transactions (via Internet/USSD/SMS), I want to make sure those clients are not tampered with and are the original ...
0
votes
1answer
75 views

Different Microsoft-signed excecutables have apparently the same signature!

On Windows 10 systems, I found two versions of bootsect.exe (a Microsoft-supplied utility that writes disk boot sector) with different hashes (SHA-1 9b7463c79460a55a36b53bee0889f894b2379ec3 for one ...
0
votes
2answers
81 views

PGP vs Hash functions

What is the difference (in terms of security strength) between checking a package' integrity using pgp and hashing functions (i.e. sha256)? Isn't pgp less secure as the verifier must trust the ...
0
votes
1answer
216 views

BLS signature java implementation needed (if possible, along with some example code)

I need to sign a string with the shortest digest possible using regular certificate like X.509. As far as I understand, I will have to transform the string to the sequence of bytes, then sign. After ...
2
votes
1answer
30 views

Signing a code and application

I want to send my application to different servers/terminals with content integrity and confidentiality. So, I need to some process to sign my code and application before sending it to servers and to ...
4
votes
1answer
62 views

What does an OpenPGP signature consist of?

I don't understand how OpenPGP signatures work. I have a picture which I want to sign, and a digital certificate which consists of my name and email address and my public key. Additionally, a digital ...
3
votes
1answer
48 views

How to acquire DNSSEC root trust anchor from IANA?

I want to establish trust in a DNSSEC record. I found, that it can be done $ dig +sigchase +trusted-key=./root.key @8.8.8.8 eesti.ee root.key could be obtained with $ dig . DNSKEY @8.8.8.8 | grep -...
0
votes
1answer
108 views

Where in the CSR is the public key?

I am reading http://www.akadia.com/services/ssh_test_certificate.html In step 2 openssl req -new -key server.key -out server.csr server.key is generated earlier using openssl genrsa -des3 -out ...
2
votes
2answers
138 views

Self-signed cert - how it works

I am new to SSL / digital certificates / signatures. What I know is that a digital signature must be verified/decrypted using the public key. So a cert that is signed by a CA must be verified/...
0
votes
1answer
51 views

Authenticating a user by verifying a signature

Background I'm setting up an API which will be used primarily over HTTPS (only calls not needing any security what so ever is available over HTTP). Some aspects of it need to be accessed only by ...
0
votes
2answers
138 views

SSL digital certificate process - high level

I am a project manager and is touching on an IT project consisting of the usual 3 tier - web/client - middleware - database. In this case, I have an web server and needs to implement SSL ...
1
vote
4answers
274 views

Use GnuPG to verify if specified user signed file

To verify if file is signed correctly we use command: gpg --verify <file_name> and the output shows if file is signed correctly. And if it is, then signer name is shown. But is there ...
10
votes
3answers
377 views

Is this a weakness of enveloped XML signature?

There might be a problem in many applications based on XML signature verification (provided I am not wrong, of course). Let's have a simple XML message with an enveloped XML signature: <?xml ...
1
vote
2answers
53 views

RSA blind signature vs signing a hash

My understanding is that the key feature of a blind RSA signature is that the signer is unaware of the contents of the message being signed. How is this different from simply hashing some data and ...
2
votes
1answer
283 views

Microsoft and SHA-1 deprecating on Windows 7

Microsoft states: Effective January 1, 2016, Windows (version 7 and higher) and Windows Server will no longer trust any code that is signed with a SHA-1 code signing certificate and that ...
15
votes
7answers
10k views

Deprecation of SHA1 code signing certificates on Windows

EDIT (7/7/2016) - see addition at the end of post I have been keenly following the issues with regards to Microsoft deprecating the use of SHA1 code-signing certificates for Windows executables (http:...
3
votes
2answers
103 views

Sign a callback URL

I have a Single Sign-On system that works this way : User clicks link on clientsite.com that redirect him to mastersite.com?returnTo=http://clientsite.com If auth is valid, the user is redirected ...
4
votes
2answers
199 views

Why would some Windows executables not have a “Digital Signatures” tab?

Why would some executable on a Windows 7 system not have a "Digital Signatures" tab? (With this question I am referring to those executables that are not part of Windows OS and to which the ...
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 ...
5
votes
2answers
212 views

How do I produce a CA signed public key?

I have a need to have somebody else encrypt secret data with my public key that I can then decrypt with my private key. I have produced an RSA private/public key pair with OpenSSL gave them the public ...
3
votes
1answer
83 views

Verification of a timestamped PDF

I'm kinda new to the process of timestamping files to provide digital integrity. For testing purposes, i use tsa.safecreative.org for PDF files. Now i've signed a couple PDF files and if i open up ...
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 ...
3
votes
2answers
145 views

Client side signing of a file(.exe,.dll,.jar..) using CA issued certificate and signtool [closed]

In a current project we have purchased certificate from a trusted CA and have installed in a host, sign tool is also installed in the same host. All the files which we develop(jar,dll,apk,exe etc..,) ...
7
votes
1answer
78 views

Subresource Integrity versus signing

The draft spec for subresource integrity is straightforward: This document specifies such a validation scheme, extending two HTML elements with an integrity attribute that contains a ...
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 ...
0
votes
1answer
24 views

Standard digital signature data representation

I am creating digital signatures using various scheme, e.g. RSASSA-PSS. The result is bytes that represents signed data with private key. I would like to store signature as a standard data ...
2
votes
1answer
102 views

Strategy for electronic document (PDF) signatures

I'm treading into the murky waters of electronic document signatures, and I'm having trouble figuring out the right approach to deal with my requirements. I think this should be pretty straightforward,...
0
votes
1answer
37 views

For X.509 Certificates where is the actual digital signature?

When you open up the certificate information from your browser and go to the details tab there is a bunch of information for various certificate fields. I am wondering which field contains the actual ...
0
votes
5answers
167 views

How to make sure nobody has read this!

Is there any computer/server which would allow me to get "guaranteed read access history" for files? For example, suppose I made a file with my plaintext passwords and simply wanted to make sure that ...
2
votes
2answers
85 views

Is this a secure Digital Signature + Encryption method?

I am trying to wrap my head around Digital Signatures and how RSA Encryption supports them. And which order to do them along with what specifically to encrypt. So say we have Alice and Bob and a ...
2
votes
1answer
54 views

what is worth a digital signature based on email address only? [closed]

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....
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. ...