How to Disable HTTPS on WAN in FortiGate Firewall

How to Disable HTTPS on WAN in FortiGate Firewall

Recently, I encountered a security alert on my FortiGate firewall indicating multiple failed admin login attempts from an unknown external IP. The log message was as follows:

 

Message meets Alert condition
The following critical firewall event was detected: Admin login failed.

date=2025-03-28 time=06:32:33 devname=XXXXX devid=FGXXXXX logid="0100032002" type="event" subtype="system" level="alert" vd="root" eventtime=XXXXXXXXXXXXXXX tz="+0800" logdesc="Admin login failed" sn="0" user="admin" ui="https(XXX.XXX.XXX.XXX)" method="https" srcip=XXX.XXX.XXX.XXX dstip=XXX.XXX.XXX.XXX action="login" status="failed" reason="name_invalid" msg="Administrator admin login failed from https(XXX.XXX.XXX.XXX) because of invalid user name"

 

This indicated an unauthorized attempt to access the FortiGate Web UI via HTTPS from the WAN interface. To mitigate this security risk, I decided to disable HTTPS administrative access on the WAN interface.

 

Why Disable HTTPS on WAN?

Exposing HTTPS management access to the internet increases the risk of brute-force attacks, unauthorized login attempts, and potential security breaches. By disabling it, we achieve:

✅ Preventing External Login Attempts – Blocks unauthorized access from the public internet.
✅ Reducing Attack Surface – Eliminates an entry point for hackers targeting admin credentials.
✅ Forcing Secure Access Methods – Encourages the use of VPN or internal network access for firewall management.

 

Steps to Disable HTTPS on WAN in FortiGate

To enhance security, I disabled HTTPS access on the WAN interface by following these steps:

Method 1: Using FortiGate Web UI

1. Log in to FortiGate Web UI from a secure internal network.
2. Navigate to Network > Interfaces.
3. Locate the WAN interface and click Edit.
4. Under Administrative Access, uncheck HTTPS and any other unnecessary services.
5. Click OK to save changes

 

Method 2: Using CLI (Command Line Interface)

Alternatively, this can be done via CLI:

 

config system interface 
    edit "wan1" 
        set allowaccess ping 
    next 
end

 

Impact of Disabling HTTPS on WAN

🔹 Pros:
✔️ Strengthens firewall security against unauthorized logins.
✔️ Prevents brute-force and credential stuffing attacks.
✔️ Limits administrative access to internal users or VPN connections.

🔸 Cons:
❌ Remote access to the FortiGate Web UI via WAN is disabled.
❌ Requires VPN or internal access to manage the firewall.

 

Conclusion

Disabling HTTPS access on WAN is a simple yet effective step to enhance firewall security and prevent unauthorized access. Instead of exposing the FortiGate management interface to the internet, it’s best to use VPN, IP restrictions, and secure authentication methods for remote access.

By implementing these security measures, I can ensure better protection for my network and minimize risks from external threats.