After Configuring SSL Decryption Mozilla Firefox Presents Certificate Error

Issue

After configuring SSL decryption Mozilla Firefox shows certificate error:

Error: (Error code: sec_error_untrusted_issuer)

See the image below for an example of this error message:

Cause

This occurs because Mozilla Firefox uses different certificate repositories than other browsers such as Internet Explorer (IE) and Google Chrome.

Resolution

To resolve the certificate error, import the root certificate used for the SSL decryption to the following location: Mozilla > Options > View Certificates > Authorities and click on Import. This will import the root certificate used for the SSL decryption, as shown below:

Once the certificate has been imported verify the 'Edit trust settings'. Make sure the following options have been selected:

Go to Options > Advanced > Certificates > View Certificates and select the certificate that was imported and select 'Edit Trust'.

In the example below, the certificate selected is 172.16.105.1:

owner: hshah