How to install Microsoft Windows CA certificate into Nessus linux?

You need a combination of these two

http://blogx.co.uk/ViewItem.asp?Entry=813
http://www.nessus.org/documentation/nessus_4.2_installation_guide.pdf

Path for the cert and key is:

/opt/nessus/com/nessus/CA/servercert.pem
/opt/nessus/var/nessus/CA/serverkey.pem


Obtain a certificate from MS CA Web - something like http://ca-server/certsrv
Click Request certificate- select advanced and then follow the dialog and save the certificate in Windows client. Type mmc and add certificate add-in, for my user.

Then you can export it in pksc12 format and then split into key and cert as:

Type "openssl pkcs12 -in filename.pfx -nocerts -nodes -out PBX_PrivateKey.pem" (you will be prompted for the password) to export the private key (no certificates at all will be output).

Then type "openssl pkcs12 -in filename.pfx -clcerts -nokeys -out PBX_Certificate.pem" to export the certificate.