HP HPE6-A78 - Aruba Certified Network Security Associate Exam

When implementing wireless containment as a response to unauthorized devices, a company should consider the legal implications. Wireless containment might affect devices that are not part of the company's network and could be considered as a form of interference. This could have legal consequences, and therefore, such actions should be carefully reviewed and ideally should be performed in a targeted and controlled manner, reducing the risk of legal issues.

HPE Aruba Networking AOS-CX switches support TACACS+ for administrative authentication, where ClearPass Policy Manager (CPPM) can act as the TACACS+ server. When an admin authenticates, CPPM sends a TACACS+ response that includes attributes such as the TACACS+ privilege level and vendor-specific attributes (VSAs) like Aruba-Priv-Admin-User.

In this scenario, CPPM sends:

TACACS+ privilege level = 15: In TACACS+, privilege level 15 is the highest level and typically grants full administrative access (equivalent to a superuser or administrator role).

Aruba-Priv-Admin-User = 1: This Aruba-specific VSA indicates that the user should be granted the highest level of administrative access on the switch.

On AOS-CX switches, the privilege level 15 maps to the administrator role, which provides full read-write access to all switch functions. The Aruba-Priv-Admin-User = 1 attribute reinforces this by explicitly assigning the admin role, ensuring the user has unrestricted access.

Option A, "The user receives auditors access," is incorrect because auditors typically have read-only access, which corresponds to a lower privilege level (e.g., 1 or 3) on AOS-CX switches.

Option B, "The user receives no access," is incorrect because the authentication was successful, and CPPM sent a response granting access with privilege level 15.

Option D, "The user receives operators access," is incorrect because operators typically have a lower privilege level (e.g., 5 or 7), which provides limited access compared to an administrator.

The HPE Aruba Networking AOS-CX 10.12 Security Guide states:

"When using TACACS+ for administrative authentication, the switch interprets the privilege level returned by the TACACS+ server. A privilege level of 15 maps to the administrator role, granting full read-write access to all switch functions. The Aruba-Priv-Admin-User VSA, when set to 1, explicitly assigns the admin role, ensuring the user has unrestricted access." (Page 189, TACACS+ Authentication Section)

Additionally, the HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide notes:

"ClearPass can send the Aruba-Priv-Admin-User VSA in a TACACS+ response to specify the administrative role on Aruba devices. A value of 1 indicates the admin role, which provides full administrative privileges." (Page 312, TACACS+ Enforcement Section)

Tunneling traffic between an Aruba switch and an Aruba Mobility Controller (MC) allows for the centralized application of firewall policies and deep packet inspection to wired clients. By directing traffic through the MC, network administrators can implement a consistent set of security policies across both wired and wireless segments of the network, enhancing overall network security posture.

The ArubaOS firewall is a stateful firewall, meaning that it can track the state of active sessions and can make decisions based on the context of the traffic. This stateful inspection capability allows it to automatically allow return traffic for sessions that it has permitted, thereby enabling seamless two-way communication for authorized users while maintaining the security posture of the network.

If clients cannot authenticate and there is no record of the authentication attempt in Aruba ClearPass Access Tracker, two possible problems that could cause this symptom are:

The RADIUS shared secret does not match between the switch and CPPM. This mismatch would prevent the switch and CPPM from successfully communicating, so authentication attempts would fail, and no record would appear in Access Tracker.

CPPM does not have a network device profile defined for the switch's IP address. Without a network device profile, CPPM would not recognize authentication attempts coming from the switch and would not process them, resulting in no logs in Access Tracker.

The other options are incorrect because:

Users logging in with the wrong credentials would still generate an attempt record in Access Tracker.

Clients configured to use a mismatched EAP method would also generate an attempt record in Access Tracker.

Clients not configured to trust the root CA certificate for CPPM's RADIUS/EAP certificate might fail authentication, but the attempt would still be logged in Access Tracker.

Social engineering in the context of network security refers to the techniques used by hackers to manipulate individuals into breaking normal security procedures and best practices to gain unauthorized access to systems, networks, or physical locations, or for financial gain. Hackers use various forms of deception to trick employees into handing over confidential or personal information that can be used for fraudulent purposes. This definition encompasses phishing attacks, pretexting, baiting, and other manipulative techniques designed to exploit human psychology. Unlike other hacking methods that rely on technical means, social engineering targets the human element of security. References to social engineering, its methods, and defense strategies are commonly found in security training manuals, cybersecurity awareness programs, and authoritative resources like those from the SANS Institute or cybersecurity agencies.

When configuring an ArubaOS-CX switch to send RADIUS debug messages to a central SIEM server, it is important to correctly direct these debug outputs. The command debug radius all activates debugging for all RADIUS processes, capturing detailed logs about RADIUS operations. If the SIEM server is already defined on the switch for logging purposes (as indicated by the command logging 10.5.6.12), the correct destination for these debug messages to be sent to the SIEM server would be through the syslog. This ensures that all generated logs are forwarded to the centralized server specified for logging, enabling consistent log management and analysis. Using syslog as the destination leverages the existing logging setup and integrates seamlessly with the network's centralized monitoring systems.

To ensure that only management stations in the subnet 192.168.1.0/24 can access the ArubaOS-Switches' Command Line Interface (CLI), Web UI, and REST interfaces, while also allowing managers to access other parts of the network, you should specify 192.168.1.0 255.255.255.0 as the authorized manager IP address on the switches. This configuration will restrict access to the switch management interfaces to devices within the specified IP address range, effectively creating a management access list.

The exhibit shows the configuration of a WLAN on an AOS-8 Mobility Controller (MC) with the following settings:

Key management: WPA3-Enterprise (indicating 802.1X authentication).

Use CNSA suite: Unchecked (using standard encryption, not the Commercial National Security Algorithm suite).

Key size: 128 bits (standard for AES-GCMP in WPA3).

Reauth interval: 1440 minutes (24 hours, the interval for re-authentication).

Machine authentication: Disabled (only user authentication is required).

Blacklisting: Disabled (clients are not blacklisted after failed attempts).

The question states that the AAA profile settings have not been adjusted, meaning the default roles (e.g., initial role, logon role, 802.1X default role) are not specified in the exhibit and are assumed to be the system defaults (e.g., "logon" for the initial and logon roles, and a default role like "guest" for the 802.1X default role). The question asks under which circumstances a client will receive the "default role assignment," which refers to the 802.1X default role configured in the AAA profile for the WLAN.

802.1X Authentication Process in AOS-8:

When a client connects to a WPA3-Enterprise WLAN, it starts in the initial role (typically "logon") to allow basic connectivity (e.g., DHCP, DNS).

During 802.1X authentication, the client is placed in the logon role to allow communication with the authentication server (e.g., ClearPass Policy Manager, CPPM).

If authentication succeeds, the client is assigned a role:

If the authentication server (e.g., CPPM) sends an Aruba-User-Role VSA with a role that exists on the MC, the client is assigned that role.

If no Aruba-User-Role VSA is sent, the client is assigned the 802.1X default role configured in the AAA profile for the WLAN.

If authentication fails or the server is unreachable, the client may be assigned a different role (e.g., a critical role, if configured) or denied access.

Option A, "The client has attempted 802.1X authentication, but the MC could not contact the authentication server," is incorrect. If the MC cannot contact the authentication server (e.g., due to a timeout), the client does not receive the 802.1X default role. Instead, the MC may apply a critical role (if configured) or deny access, depending on the configuration. The 802.1X default role is applied only after successful authentication.

Option B, "The client has passed 802.1X authentication, and the authentication server did not send an Aruba-User-Role VSA," is correct. If the client successfully authenticates via 802.1X and the authentication server (e.g., CPPM) does not send an Aruba-User-Role VSA, the MC assigns the client the 802.1X default role configured in the AAA profile for the WLAN. This is the "default role assignment" referred to in the question.

Option C, "The client has attempted 802.1X authentication, but failed to maintain a reliable connection, leading to a timeout error," is incorrect. A timeout error during authentication (e.g., the client fails to respond to EAP messages) typically results in an authentication failure, not a successful authentication. The client would not receive the 802.1X default role; it might be denied access or placed in a different role (e.g., a pre-authentication role).

Option D, "The client has passed 802.1X authentication, and the value in the Aruba-User-Role VSA matches a role on the MC," is incorrect. If the authentication server sends an Aruba-User-Role VSA with a role that exists on the MC, the client is assigned that specific role, not the 802.1X default role.

The HPE Aruba Networking AOS-8 8.11 User Guide states:

"After a client successfully authenticates via 802.1X, the Mobility Controller assigns a role to the client. If the authentication server (e.g., a RADIUS server) sends an Aruba-User-Role VSA with a role that exists on the controller, the client is assigned that role. If no Aruba-User-Role VSA is sent in the Access-Accept message, the client is assigned the 802.1X default role configured in the AAA profile for the WLAN. For example, if the AAA profile specifies ‘guest’ as the 802.1X default role, the client will be assigned the ‘guest’ role." (Page 305, Role Assignment Section)

Additionally, the HPE Aruba Networking Wireless Security Guide notes:

"In WPA3-Enterprise with 802.1X authentication, the default role assignment occurs when a client successfully authenticates but the authentication server does not specify a role via the Aruba-User-Role VSA. In this case, the client receives the 802.1X default role defined in the AAA profile, such as ‘guest’ or another role configured by the administrator." (Page 42, 802.1X Role Assignment Section)

HPE Aruba Networking ClearPass Policy Manager (CPPM) uses TCP fingerprinting as a passive profiling method to classify endpoints by analyzing TCP packet headers (e.g., TTL, window size) to identify the operating system (e.g., Windows, Linux). The company in this scenario has Mobility Controllers (MCs), campus APs, and AOS-CX switches, and wants to use CPPM’s TCP fingerprinting capabilities for endpoint classification.

TCP Fingerprinting: This method requires CPPM to receive TCP traffic from endpoints. Since CPPM is not typically inline with network traffic, the traffic must be mirrored to CPPM for analysis. This is often done using a SPAN (Switched Port Analyzer) port or mirror port on a switch or controller.

Option A, "You will need to mirror traffic to one of CPPM’s span ports from a device such as a core routing switch," is correct. For CPPM to perform TCP fingerprinting, it needs to see the TCP traffic from endpoints. This is typically achieved by mirroring traffic from a core routing switch (or another device like an MC) to a SPAN port on the CPPM server. For example, on an AOS-CX switch, you can configure a mirror session with the command mirror session 1 destination interface source vlan to send traffic to CPPM. This is a key consideration for enabling TCP fingerprinting.

Option B, "ClearPass admins will need to provide the credentials of an API admin account to configure on HPE Aruba Networking devices," is incorrect. TCP fingerprinting does not require API credentials. It is a passive profiling method that analyzes mirrored traffic, and no API interaction is needed between CPPM and Aruba devices for this purpose.

Option C, "AOS-CX switches do not offer the support necessary for CPPM to use TCP fingerprinting on wired endpoints," is incorrect. AOS-CX switches support mirroring traffic to CPPM (e.g., using a mirror session), which enables CPPM to perform TCP fingerprinting on wired endpoints. The switch does not need to perform the fingerprinting itself; it only needs to send the traffic to CPPM.

Option D, "TCP fingerprinting of wireless endpoints requires a third-party Mobility Device Management (MDM) solution," is incorrect. TCP fingerprinting is a built-in capability of CPPM and does not require an MDM solution. For wireless endpoints, the MC can mirror client traffic to CPPM (e.g., using a datapath mirror), allowing CPPM to perform TCP fingerprinting.

The HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide states:

"TCP fingerprinting requires ClearPass to receive TCP traffic from endpoints for analysis. A key consideration is that you must mirror traffic to one of ClearPass’s SPAN ports from a device such as a core routing switch or Mobility Controller. For example, on an AOS-CX switch, configure a mirror session with mirror session 1 destination interface source vlan to send traffic to ClearPass for TCP fingerprinting." (Page 248, TCP Fingerprinting Section)

Additionally, the HPE Aruba Networking AOS-8 8.11 User Guide notes:

"For ClearPass to perform TCP fingerprinting on wireless endpoints, the Mobility Controller can mirror client traffic to ClearPass using a datapath mirror. For wired endpoints, an AOS-CX switch can mirror traffic to ClearPass’s SPAN port, enabling TCP fingerprinting without requiring additional support on the switch itself." (Page 351, Device Profiling with CPPM Section)