InformationIn most cases, a browser HTTPS interface is used to administer the Palo Alto appliance. The certificate used to secure this session should satisfy the following criteria:
1. A valid certificate from a trusted source should be used. While a certificate from a trusted Public Certificate Authority is certainly valid, one from a trusted Private Certificate Authority is absolutely acceptable for this purpose.
2. The certificate should have a valid date. It should not have a "to" date in the past (it should not be expired), and should not have a "from" date in the future.
3. The certificate should use an acceptable cipher and encryption level.
If a certificate that is self-signed, expired, or otherwise invalid is used for the browser HTTPS interface, administrators in most cases will not be able to tell if their session is being eavesdropped on or injected into by a "Man in the Middle" attack.
NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.
SolutionIf a new administrative certificate is needed, acquire a certificate that meets the stated criteria and set it:
Optional: Navigate to Device > Certificate Management > Certificates
Import an appropriate Certificate for your administrative session, from a trusted Certificate Authority.
Navigate to Device > Certificate Management > SSL/TLS Service Profile
Choose or import the certificate you want to use for the web based administrative session.
Navigate to 'Device > Setup > Management > General Settings > SSL/TLS Service Profile'
Choose the Service Profile that you have configured
If the default self-signed certificate is used, an administrator will not be able to clearly tell if their HTTPS session is being hijacked or not. Using a trusted certificate ensures that the session is both encrypted and trusted.
A self-signed certificate is installed by default for the administrative interface.