Pass the Fortinet Fortinet Network Security Expert NSE4_FGT_AD-7.6 Questions and answers with CertsForce

Based on the exhibit and the FortiOS 7.6 SSL/SSH Inspection documentation, the correct answer is C.

Understanding the Exhibit Configuration

In the SSL/SSH Inspection Profile, the following settings are shown:

Inspection method: Full SSL Inspection

Server certificate SNI check: Strict

This setting directly controls how FortiGate validates the Server Name Indication (SNI) provided by the client during the TLS handshake.

FortiOS 7.6 Behavior of “Server certificate SNI check”

FortiOS supports three modes for Server certificate SNI check:

Disable

No validation between SNI and server certificate.

Enable

FortiGate checks SNI against the certificate.

If mismatch occurs, FortiGate may still allow the session with reduced validation.

Strict

FortiGate enforces a strict match.

The SNI must match either the CN (Common Name) or one of the SAN (Subject Alternative Name) entries in the server certificate.

If the SNI does not match either CN or SAN, the TLS session is immediately terminated.

The exhibit clearly shows Strict selected.

Why Option C is Correct

With Strict enabled, FortiGate rejects the TLS connection when:

The SNI does not match the CN, and

The SNI does not match any SAN entry

This results in the connection being closed, not allowed with warnings or fallback behavior.

Therefore:

C. FortiGate will close the connection if the SNI does not match the CN or SAN fields is exactly the documented behavior.

Why the Other Options Are Incorrect

A: FortiGate does not fall back to using the CN for URL filtering when Strict is enabled.

B: There is no “accept with warning” behavior in Strict mode.

D: Incorrect logical condition. FortiGate does not require mismatch with both CN and SAN simultaneously; a mismatch with either valid field set is sufficient to close the connection.

From the exhibits, there are three relevant firewall policies from LAN (port4) to WAN (port2), each using a different IP pool for source NAT:

TCP traffic

Service: ALL_TCP

Destination: BR1-FGT

IP Pool: SNAT-Pool → 100.65.0.49

PING traffic

Service: PING

Destination: all

IP Pool: SNAT-Remote1 → 100.65.0.99

IGMP traffic

Service: IGMP

Destination: all

IP Pool: SNAT-Remote → 100.65.0.149

The user on HQ-PC-1 (10.0.11.50) is pinging BR1-FGT (100.65.1.111). In FortiOS, policy matching is based on (among other fields) source, destination, and service, and the first matching policy in top-down order is applied.

Because the traffic is ICMP echo (ping), it matches the policy named PING traffic (service PING, destination all). That policy explicitly uses Use Dynamic IP Pool with SNAT-Remote1, which is configured with external IP 100.65.0.99.

Therefore, the source NAT IP used for this ping is 100.65.0.99.

Based on the FortiOS 7.6 Infrastructure and IPsec VPN documentation, Dead Peer Detection (DPD) can be configured in three primary modes: On Demand, On Idle, and Disabled.

On Demand (Default Mode): This mode is specifically designed to minimize unnecessary traffic. In this mode, FortiGate sends DPD probes only when there is no inbound traffic but the FortiGate is attempting to send outbound traffic. Because network communication is typically bidirectional, the absence of inbound traffic while outbound traffic is being sent is a primary indicator of a potentially dead tunnel. This matches the specific requirement described in the question.

On Idle: In this mode, DPD probes are sent if no traffic (neither inbound nor outbound) has been observed in the tunnel for a specific period. It verifies the tunnel status even when the connection is completely idle.

Enabled: In older versions or specific CLI contexts, "Enabled" may refer to periodic DPD, but in the current FortiOS 7.x/7.6 GUI and CLI terminology for Phase 1 settings, the active modes are defined as on-demand or on-idle.

Disabled: In this mode, the FortiGate does not send DPD probes but will still respond to DPD probes sent by the remote peer.

The requirement that the administrator wants probes sent only when there is no inbound traffic (usually implying the FortiGate is sending but not receiving) is the fundamental definition of the On Demand mechanism in the Fortinet curriculum.

In FortiOS 7.6, the Antivirus scan master switch in an antivirus profile becomes available only after at least one supported protocol is enabled for inspection.

What the exhibit shows

A new antivirus profile named FTP_AV_Profile

Feature set: Flow-based

Antivirus scan switch is grayed out

All Inspected Protocols (HTTP, SMTP, POP3, IMAP, FTP, CIFS) are currently disabled

Why the Antivirus scan switch is grayed out

In FortiOS antivirus profiles:

The Antivirus scan toggle is a dependent control

It cannot be enabled unless at least one inspected protocol is selected

This prevents enabling AV scanning when there is no traffic type to scan

This behavior is documented in the FortiOS 7.6 Antivirus Profile configuration section.

Once you enable a protocol (for example, FTP), the Antivirus scan switch becomes active and configurable.

Why option B is correct

B. None of the inspected protocols are active in this profile.

All protocol toggles are OFF

Therefore, FortiGate disables (grays out) the Antivirus scan option

This is expected and correct behavior

Why the other options are incorrect

A. Antivirus scan is disabled under Feature visibilityIncorrect. Feature Visibility controls whether Antivirus appears in the GUI, not whether the scan switch is enabled inside a profile.

C. Feature set must be Proxy-basedIncorrect. Antivirus scanning is supported in both flow-based and proxy-based modes.

D. Less than 2 GB RAM does not support Antivirus scanIncorrect. Memory size affects performance and offloading, not basic AV scan availability.

In FortiSASE Secure Internet Access (SIA) agent-based mode, traffic steering and security enforcement rely on components integrated with the FortiClient agent.

Components used in SIA agent-based mode

A. FortiSASE Firewall-as-a-Service (FWaaS)

Correct.

FWaaS is a core security component of FortiSASE.

It enforces firewall policies, security inspection, and access control for agent-based users.

All user traffic tunneled by the agent is inspected by FWaaS.

C. VPN policies

Correct.

In agent-based mode, the FortiClient establishes a secure tunnel to FortiSASE.

VPN policies define:

Authentication

Access control

Traffic steering

These policies are fundamental to agent-based connectivity.

Why the other options are incorrect

B. Proxy auto-configuration (PAC) filePAC files are used in agentless or proxy-based modes, not agent-based SIA.

D. FortiExtenderFortiExtender is a WAN extension device and is unrelated to FortiSASE SIA agent-based architecture.

According to the FortiOS 7.6 Administrator Study Guide, while there is a global administrative idle timeout setting that applies to all users by default (typically 5 minutes), FortiOS allows for granular control through Administrator Profiles. The Override Idle Timeout feature is specifically designed to allow different timeout values for different access profiles, which is ide1al for environments like a Network Operations Center (NOC) where persistent monitoring is required.23

To implement this, the administrator must modify the s4pecific access profile settings. By using the command config system accprofile 5and editing the NOC_Access profile, the administrator can enable the admintimeout-override and then increase the admintimeout value (Statement D). This configuration ensures that only the users assigned to that specific profile benefit from the extended session duration, maintaining a higher security posture for other administrative accounts that still follow the global timeout. Other options, such as changing the profile order (A) or assigning the super_admin role (C), do not address the specific requirement for inactivity timeout management. Option B is incorrect as "offline value" is not a standard parameter for this feature.

In FortiOS 7.6, the predefined deep-inspection and custom-deep-inspection SSL inspection profiles intentionally exclude certain web categories (such as Finance and Banking and Health and Wellness) and well-known domains (for example, Apple, Google, Adobe). This behavior is documented and intentional.

The two correct reasons are:

B. The legal regulation aims to prioritize user privacy and protect sensitive information for these websites.

Correct

Categories like Finance and Banking and Health and Wellness commonly handle highly sensitive personal data.

Many privacy and compliance regulations (for example, GDPR, PCI-DSS, HIPAA-like requirements) discourage or restrict SSL interception for such traffic.

To reduce legal and compliance risks, FortiOS exempts these categories from deep SSL inspection by default.

This is explicitly stated in FortiOS SSL/SSH Inspection documentation.

C. These websites are in an allowlist of reputable domain names maintained by FortiGuard.

Correct

FortiGuard maintains a reputable/trusted domain list for well-known services and platforms.

These domains are excluded from deep inspection by default to:

Prevent application breakage

Avoid certificate pinning and compatibility issues

Maintain user experience

This is why domains such as Apple, Google, Adobe, and app stores appear under SSL inspection exemptions.

Why the other options are incorrect

A. Resource utilization optimization

Incorrect.

While reduced inspection can save resources, this is not the primary documented reason for exempting these categories.

D. FortiGate temporary certificate denies access to HSTS websites

Incorrect.

Although HSTS and certificate pinning can cause issues with SSL inspection, this option describes a side effect, not the reason for exemption.

The exemption exists to avoid such problems, not because the certificate denies access.