How to tamper a X509 format certificate?

5
votes

I used openssl command line tool to generate a CA signed certificate. now I need to tamper it to generate the signature mismatch error.

Is there any tool available to tamper the X509 certificate.

1
opensslx509certificatepki
here are the locations of the stores, if you are using Windows. msdn.microsoft.com/en-us/library/windows/desktop/… . Find your store and look for a key that matches your thumbprint. If you modify the blob i think that should do it. – Brandon.Staley
@Brandon.Staley can you tell me how to modify the blob – Balamurugan

1 Answers

6
votes

Open certificate file in ASN.1 Editor, find commonName node, right-click it and choose "Edit...":

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Change the text of commonName field:

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Hit OK, save your changes and there you are:

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