HP HPE7-A02 - Aruba Certified Network Security Professional Exam

In HPE Aruba Networking ClearPass Device Insight (CPDI), a device with a Risk Score of 90 indicates that the posture is unhealthy, and CPDI has detected at least one vulnerability on the device. The risk score is a reflection of the device's security posture and detected vulnerabilities. A high risk score, such as 90, typically signifies significant security concerns, including the presence of vulnerabilities that could be exploited, thereby categorizing the device as a high-risk asset within the network.

OCSP (Online Certificate Status Protocol):

OCSP allows a device to check the revocation status of a specific certificate in real-time by querying the Certificate Authority (CA).

This is more efficient than downloading an entire Certificate Revocation List (CRL), as it only checks the status of one certificate.

Option Analysis:

Option A: Incorrect. Root certificates are still required to validate the CA issuing the certificate.

Option B: Correct. OCSP checks the status of a single certificate for revocation.

Option C: Incorrect. Downloading all serial numbers is a function of a CRL, not OCSP.

Option D: Incorrect. OCSP does not handle certificate renewal; it only checks for revocation.

RADIUS Change of Authorization (CoA):

CoA is triggered when ClearPass determines that a client’s posture status has changed (e.g., Healthy, Quarantine).

The RADIUS enforcement policy is where you configure actions and enforcement profiles that respond to these posture changes.

Option Analysis:

Option A: Correct. RADIUS enforcement policies are used to configure actions, including triggering CoA.

Option B: Incorrect. OnGuard settings configure posture agent behavior, not enforcement rules.

Option C: Incorrect. The posture policy evaluates compliance but does not trigger CoA.

Option D: Incorrect. WEBAUTH enforcement policies are for web-based authentication, not posture-related CoA.

In a client-to-site VPN based on tunnel-mode IPsec, the remote clients and a gateway at the main site are responsible for the IPsec encapsulation. The remote clients initiate the VPN connection and encapsulate their traffic in IPsec, which is then decapsulated by the gateway at the main site.

1.IPsec Encapsulation: The remote clients encapsulate their traffic using IPsec protocols before sending it over the internet to the main site.

2.Gateway Role: The gateway at the main site receives the encapsulated traffic, decapsulates it, and forwards it to the internal network. Similarly, traffic from the main site to the remote clients is encapsulated by the gateway and decapsulated by the clients.

3.Security: This setup ensures that data is securely transmitted between the remote clients and the main site, protecting it from eavesdropping and tampering.

When setting up a ClearPass cluster, it is critical to ensure secure communication between the cluster nodes and the client devices. For this purpose, certain certificates must be properly configured.

1. Why HTTPS Requires a CA-Signed Certificate?

HTTPS communication is used for inter-cluster communication and for the web-based user interface that administrators use to manage the ClearPass cluster.

Before joining the cluster, it is strongly recommended to install a CA-signed HTTPS certificate on the Subscriber to ensure secure communication and prevent warnings/errors due to untrusted certificates.

Without a CA-signed certificate, the Subscriber might use a self-signed certificate, leading to security risks and lack of trust validation.

2. Analysis of Other Certificate Types

B. Database:

Incorrect: Database communications within ClearPass clusters are secured using internal certificates or keys. These are not user-facing and do not require a CA-signed certificate before joining the cluster.

C. RADIUS/EAP:

Incorrect: RADIUS/EAP certificates are important for client authentication, but they are not required on the Subscriber prior to cluster joining. These can be configured after the Subscriber is part of the cluster.

D. RadSec:

Incorrect: RadSec is an optional feature for secure RADIUS communication over TLS, and its certificate configuration is typically performed post-cluster setup.

Final Recommendation

To ensure secure cluster operations and seamless web-based management, a CA-signed HTTPS certificate should be installed on the Subscriber before it joins the ClearPass cluster.

References

ClearPass Deployment Guide for Version 6.9.

Best Practices for Certificate Management in ClearPass Clusters.

HPE Aruba ClearPass Cluster Configuration Guide.

User-Based Tunneling (UBT) with VRRP:

UBT allows traffic from authenticated users to be tunneled to an HPE Aruba Networking gateway.

In the case of VRRP, where two gateways are configured for redundancy, the AOS-CX switch will always send the traffic to the primary gateway defined in the UBT zone configuration.

The VRRP state (master/backup) does not impact the UBT decision; the UBT primary configuration takes precedence.

Option Analysis:

Option A: Incorrect. UBT does not strictly follow the VRRP master; it adheres to the UBT primary gateway configuration.

Option B: Correct. The switch tunnels all traffic to the primary gateway configured in the UBT zone.

Option C: Incorrect. UBT does not load-share traffic between gateways.

Option D: Incorrect. UBT uses the primary gateway configured in the UBT zone, not dynamically determined active devices.

Implementing user-based tunneling (UBT) on AOS-CX switches is beneficial for applying enhanced security features such as deep packet inspection (DPI) to wired traffic. UBT allows the traffic from specific users or devices to be tunneled to a central controller or security appliance where advanced security policies, including DPI, can be applied. This approach ensures that even wired traffic benefits from the same level of security and inspection typically available for wireless traffic, thus enhancing overall network security.

To capture traffic from a particular wireless client for a 15-minute period and then send the traffic in a PCAP file, you should go to the client's AP in HPE Aruba Networking Central and use the "Security" page to run a packet capture. This method allows you to directly capture the client's traffic from the AP managing the wireless connection, ensuring that you gather the relevant traffic data for analysis.

1.Centralized Management: HPE Aruba Networking Central provides a centralized interface for managing and monitoring APs, making it easy to initiate packet captures.

2.Security Page: The "Security" page in Aruba Central includes tools for running packet captures, allowing you to specify the duration and other parameters.

3.Ease of Use: This approach simplifies the process by using the built-in features of Aruba Central, avoiding the need for complex CLI commands or additional hardware.

Zero Trust Security is a security model that operates on the principle that no entity, whether inside or outside the network, should be trusted by default. Instead, every access request is thoroughly verified before granting access to resources. This model emphasizes protecting resources rather than merely securing the network perimeter, acknowledging that threats can originate both inside and outside the network.

1.Resource Protection: Zero Trust focuses on securing individual resources, assuming that threats can bypass traditional perimeter defenses.

2.Verification: Every access request is authenticated and authorized regardless of the source, ensuring that only legitimate users can access sensitive resources.

3.Modern Security Approach: This model aligns with the evolving threat landscape where insider threats and advanced persistent threats are common.

The "Detect Valid SSID Misuse" event in Aruba's Wireless Intrusion Detection System (WIDS) indicates that a valid SSID, associated with your network, is being broadcast from an unauthorized source. This scenario often signals a potential rogue access point attempting to deceive clients into connecting to it (e.g., for credential harvesting or man-in-the-middle attacks).

1. Explanation of Each Option

A. Clients are failing to authenticate to corporate SSIDs. You should first check for misconfigured authentication settings and then investigate a possible threat:

Incorrect:

This event is not related to authentication failures by legitimate clients.

Misconfigured authentication settings would lead to events like "authentication failures" or "radius issues," not "valid SSID misuse."

B. Admins have likely misconfigured SSID security settings on some of the company's APs. You should have them check those settings:

Incorrect:

This event refers to an external device broadcasting your SSID, not misconfiguration on the company’s authorized APs.

WIDS differentiates between valid corporate APs and rogue APs.

C. Hackers are likely trying to pose as authorized APs. You should use the detecting radio information and immediately track down the device that triggered the event:

Correct:

This is the most likely cause of the "detect valid SSID misuse" event. A rogue AP broadcasting a corporate SSID could lure clients into connecting to it, exposing sensitive credentials or traffic.

Immediate action includes:

Using the radio information from the event logs to identify the rogue AP's location.

Physically locating and removing the rogue device.

Strengthening WIPS/WIDS policies to prevent further misuse.

D. This event might be a threat but is almost always a false positive. You should wait to see the event over several days before following up on it:

Incorrect:

While false positives are possible, "valid SSID misuse" is a critical security event that should not be ignored.

Delaying action increases the risk of successful attacks against your network.

2. Recommended Steps to Address the Event

Review Event Logs:

Gather details about the rogue AP, such as SSID, MAC address, channel, and signal strength.

Locate the Rogue Device:

Use the detecting AP's radio information and signal strength to triangulate the rogue AP's physical location.

Respond to the Threat:

Remove or disable the rogue device.

Notify the security team for further investigation.

Prevent Future Misuse:

Strengthen security policies, such as enabling client whitelists or enhancing WIPS protection.

References

Aruba WIDS/WIPS Configuration and Best Practices Guide.

Aruba Central Security Event Analysis Documentation.

Wireless Threat Management Using Aruba Networks.