Generate Co-Signed File

Co-Sign File

This tool adds a signature to a file that has already been signed using a PKCS #7: Cryptographic Message Syntax (CMS) digital signature using a detached/external signed-data structure (see here). The signature is added to the existing signed-data structure which is appended to the beginning of the file. The co-signing certificate is included in the signed-data structure. The issuing CA certificate of the co-signing certificate may also be included.

File To Co-Sign

Select signed file to be co-signed:

Signer

Add alternate signature

Select co-signing certificate file:

Select co-signing certificate private key file:

Warning: private keys uploaded to this tool should ONLY be used for test and development purposes.

Select co-signing certificate alternate private key file:

Warning: private keys uploaded to this tool should ONLY be used for test and development purposes.

Set signing time (GMT):

The date and time should be entered in Greenwich Mean Time (GMT). If needed, an example of a GMT converter can be found here.

Include issuing CA certificate in signature header

HCC Crypto