Palo Alto - The server's X.509 certificate cannot be trusted


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L1 Bithead

Palo Alto - The server's X.509 certificate cannot be trusted

We used Nessus tool to run security scan on the PA-5020 & PA-3020 series & it identified with the following below medium vulnerability:


The server's X.509 certificate cannot be trusted.


Please let me know, for any fix to this vulnerability.

Cyber Elite


The management interface on the firewalls doesn't have a trusted certificate, or Nessus does not trust the certificate being used. This could be because you simply haven't installed a certificate for the GUI to utilize which is trusted by your CA, or that Nessus doesn't trust your CA.

L1 Bithead

Thanks for the update, please let me know if it is possible to install internal CA certificate for Palo Alto Web-GUI. In case if internal CA certificate is supported, please share the KB article.

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