Free Paloalto Networks PCNSE Practice Exam with Questions & Answers | Set: 8

For a network security administrator to authenticate and identify a user with a new BYOD-type device that is not joined to the corporate domain, the most effective method is to use an Authentication policy targeting users not yet identified by the system.

A. an Authentication policy with 'unknown' selected in the Source User field:

An Authentication policy allows the firewall to challenge unidentified users for credentials. By selecting 'unknown' in the Source User field, the policy targets users who have not yet been identified by the firewall, which would include users on new BYOD devices not joined to the domain.

Once the user provides valid credentials, the firewall can authenticate the user and map their identity to subsequent sessions, enabling the application of user-based policy rules and monitoring.

This approach ensures that new and unknown devices can be properly authenticated and identified without compromising security or requiring the device to be part of the corporate domain.

The GlobalProtect VPN solution by Palo Alto Networks is designed to provide secure remote access to users. It primarily attempts to establish a VPN tunnel using the IPSec protocol for optimal security and performance. However, in cases where IPSec cannot be used due to network restrictions or other issues, GlobalProtect has a fallback mechanism.

C. It tries to establish a tunnel to the GlobalProtect gateway using SSL/TLS:

If the GlobalProtect app fails to establish an IPSec tunnel with the GlobalProtect gateway, the default behavior is to fallback to SSL/TLS for tunnel establishment. This ensures that the VPN connection can still be established, maintaining secure remote access for the user even in environments where IPSec is not feasible. SSL/TLS provides a secure tunnel, albeit generally with slightly less efficiency than IPSec.

This fallback mechanism is part of the GlobalProtect app's design to ensure reliability and continuous secure access for remote users under various network conditions.

To prevent the import from affecting ongoing traffic when you import the configuration of an HA pair into Panorama, you should disable config sync on both firewalls. Config sync is a feature that enables the firewalls in an HA pair to synchronize their configurations and maintain consistency. However, when you import the configuration of an HA pair into Panorama, you want to avoid any changes to the firewall configuration until you verify and commit the imported configuration on Panorama. Therefore, you should disable config sync before importing the configuration, and re-enable it after committing the changes on Panorama12. References: Migrate a Firewall HA Pair to Panorama Management, PCNSE Study Guide (page 50)

https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-admin/high-availability/ha-concepts/ha-timers

When configuring Quality of Service (QoS) policies, particularly for traffic going to or from specific IP addresses and involving NAT, it's important to base the rule on how the firewall processes the traffic. For QoS, the firewall evaluates traffic using pre-NAT IP addresses and zones because QoS policies typically need to be applied before the NAT action occurs. This is especially true for inbound traffic, where the goal is to limit bandwidth before the destination IP is translated.

The correct combination for a QoS rule in this scenario, where the aim is to limit bandwidth for downloads from a specific server (implying inbound traffic to the server), would be:

D. Pre-NAT source IP address Pre-NAT source zone:

Pre-NAT source IP address: This refers to the original IP address of the client or source device before any NAT rules are applied. Since QoS policies are evaluated before NAT, using the pre-NAT IP address ensures that the policy applies to the correct traffic.

Pre-NAT source zone: This is the zone associated with the source interface before NAT takes place. Using the pre-NAT zone ensures that the QoS policy is applied to traffic as it enters the firewall, before any translations or routing decisions are made.

By configuring the QoS rule with pre-NAT information, the firewall can accurately apply bandwidth limitations to the intended traffic, ensuring efficient use of network resources and mitigating the impact of large file downloads from the specified server.

For detailed guidelines on configuring QoS policies, refer to the Palo Alto Networks documentation, which provides comprehensive instructions and best practices for managing bandwidth and traffic priorities on the network.

Advanced WildFire analyzes both the webpage linked by the URL and any files (like PE files) that are downloaded as a result of clicking that link. This includes checking the linked webpage for malicious content and sending any downloaded files for further analysis to determine their behavior and potential malicious intent.

The PCNSA Study Guide outlines that WildFire inspects and analyzes both content downloaded and webpages involved when integrated into the organization's security profile​. This dual-layered approach ensures comprehensive protection against threats from both the webpage and its payloads.

Step-by-Step Explanation

Link Clicked and File Download Triggered:

When the user clicks the link, their action initiates the download of a file, in this case, a Portable Executable (PE) file.

URL Inspection by WildFire:

The URL is immediately inspected for potential threats. This involves analyzing the webpage associated with the link to detect:

Known malicious indicators.

Suspicious elements like embedded scripts, links, or calls to external resources.

Forwarding the PE File for Analysis:

The PE file downloaded as a result of clicking the link is sent to the WildFire cloud or on-premises appliance for detailed behavior-based analysis.

Dynamic and Static Analysis:

Static Analysis: WildFire examines the PE file's attributes without executing it, looking for:

Suspicious code patterns.

Known malicious signatures.

Anomalous PE header details (e.g., timestamp irregularities, unexpected sections).

Dynamic Analysis: The file is executed in a controlled virtual environment to observe:

Behavioral anomalies, like privilege escalation attempts.

Network communication, such as connections to Command and Control (C2) servers.

File system modifications or registry changes indicative of malicious intent.

Threat Verdict:

Based on its findings, WildFire classifies the URL and PE file into one of the following categories:

Benign.

Grayware.

Malware.

Phishing.

Automated Response:

If either the webpage or the PE file is deemed malicious, the firewall takes predefined actions:

Blocking access to the webpage.

Quarantining or blocking the downloaded file.

Generating a detailed alert or log entry for administrators.

Signature Update:

WildFire automatically creates a signature for the detected threat and distributes it globally. This ensures that other systems in the WildFire network are protected against the same threat.

Advanced WildFire Configuration and Behavior

Forwarding File Types:

The WildFire analysis profile must be configured to forward relevant file types. In this case:

PE files are commonly forwarded by default since they are a known vector for malware.

Administrators can define custom forwarding rules based on file type and traffic.

Integration with the Security Profile:

WildFire integrates with other security profiles (e.g., Antivirus, Anti-Spyware, URL Filtering).

URL Filtering ensures that the link itself is categorized and blocked if malicious.

WildFire's output informs and updates the threat prevention database dynamically.

Why the Answer is B?

WildFire performs dual analysis:

The linked webpage is checked for malicious scripts or phishing attempts.

The PE file downloaded is analyzed for malware through both static and dynamic methods.

This layered analysis ensures robust protection against modern threats, which often combine malicious webpages with harmful payloads.

Document References:

PCNSA Study Guide: Domain 4, Section 4.1.5 ("WildFire Analysis") explains the WildFire analysis process in detail, emphasizing its role in inspecting files and URLs for malicious behavior​.

Palo Alto Networks WildFire Admin Guide:

This guide details file forwarding configurations, supported file types, and the global signature distribution process.

PAN-OS Admin Guide:

Sections on Security Profiles and URL Filtering elaborate on how WildFire integrates with other threat prevention mechanisms.