App-ID content updates from Palo Alto Networks provide the firewall with the latest application signatures. When an update is installed, new applications are automatically identified and classified based on the new signatures provided. This can directly impact how existing Security policy rules are enforced. For instance, traffic that was previously unidentified and permitted might now be identified as a specific application and blocked by an existing rule, or an application's category might change, causing it to match a different policy rule.

B. After an application content update, new applications must be manually classified prior to use

This is incorrect. The core purpose of App-ID content updates is to deliver pre-classified application signatures, enabling the firewall to automatically identify and classify new applications.

C. Existing security policy rules are not affected by application content updates

This is incorrect. Updates can re-categorize existing applications or identify previously unknown traffic, which can directly alter how existing Security policy rules enforce traffic control.

1. Palo Alto Networks PAN-OS® Administrator’s Guide 11.0 (Nova)

Chapter: Content Updates

Section: Manage New App-IDs Introduced in Content Releases.

Supporting A & C: The guide states

"New and modified App-IDs can change how your firewall enforces your existing Security policy. For example

a new App-ID might be for an application that was previously unidentified and allowed by a liberal security rule. After the update

the firewall will identify the application and block it if you have a security rule that blocks that application." This confirms that updates can change enforcement and directly affect existing rules.

2. Palo Alto Networks PAN-OS® Administrator’s Guide 11.0 (Nova)

Chapter: Content Updates

Section: App-ID and Threat Content Updates.

Supporting D & B: This section explains that Palo Alto Networks constantly develops new application signatures and makes them available for download. It states

"The firewall uses the latest application and threat signatures (content) to secure your network." This highlights the automatic nature of identification and classification provided by the updates

negating the need for manual classification of new apps.