For advanced users or those with administrative privileges, here are some general insights:
The most common method for individual users is routing traffic through an external server. By using a Virtual Private Network (VPN) or a secure proxy, the traffic is encrypted before it hits the FortiGate firewall. Since the firewall cannot inspect the encrypted payload of the VPN tunnel, it often cannot apply specific IPS signatures to the traffic [3, 4]. 2. HTTPS/SSL Inspection Gaps
If you are facing a screen, it means the FortiGate firewall has identified the site as a potential security risk, a violation of company policy, or an uncategorized website.
Wrapping web application payloads in Base64 or Hex formatting forces the IPS to have a specific decoder active for that exact traffic sub-stream. If it doesn't, the block page is bypassed.
: Switch to a personal mobile hotspot or cellular data to bypass the local network restrictions entirely. VPNs and Proxies : Use a Virtual Private Network (VPN) like For advanced users or those with administrative privileges,
However, sometimes legitimate traffic is blocked, or administrators need to bypass the system for testing or specific network architectural needs.
If a protocol anomaly is causing the block (such as an application using non-standard HTTP ports), adjust the service profile. Go to > Firewall Policy .
Go to Google Translate, paste the URL of the blocked site, and click the link in the translated box. Google will fetch the page, and the firewall often sees it as a request to Google, not the blocked site. Why You Might Be Seeing a "Certificate Not Trusted" Error
The Tor Browser anonymizes your internet traffic by routing it through a network of volunteer-operated servers. This can help in circumventing network restrictions but might be considered a more extreme measure due to its association with privacy and anonymity. If it doesn't, the block page is bypassed
Creating a dynamic port forwarding tunnel ( ssh -D ) routes your browser or testing tools through an encrypted SSH channel to a remote VPS, leaving the local FortiGuard blind to the final destination data.
Locate the log entry corresponding to the blocked timestamp, source IP, or destination IP.
If you're a network administrator or an authorized user trying to access a resource that's being blocked:
Tools like Nikto, SQLmap, and Metasploit carry distinct default headers. Modifying your testing tools to mimic standard web browsers (e.g., a standard Mozilla/5.0 Chrome string) can immediately bypass basic application-control rules built into FortiGuard profiles. Remediating IPS Bypasses (The Defender’s Perspective) encrypted connection to resolve domain names
If you are an end-user, you must submit a ticket to your IT department or network administrator to request an exception. If you are the network administrator, you can use the following native FortiOS methods to safely bypass the restriction for legitimate traffic: 1. Create a Static URL Filter Override
Proxies act as intermediaries. The Tor Browser is particularly effective as it routes traffic through multiple nodes, making it nearly impossible for traditional web filters to identify the destination.
FortiGuard often blocks sites by manipulating DNS responses. Using DoH forces your browser to use a secure, encrypted connection to resolve domain names, bypassing local network DNS interception.