This tweet from a user is asking about bypassing firewall rules in Vercel, a cloud platform for hosting projects. The user wants to create a system bypass firewall rule for another project hosted in Vercel, but faces a challenge because the CIDR ranges — the IP address ranges allowed or blocked — for Vercel hosted projects are not clearly provided. The user wonders if the workaround to bypass firewall restrictions would be to create a custom WAF (Web Application Firewall) rule that matches requests based on host or user-agent instead of CIDR IP ranges.
In simple terms, firewall rules often rely on IP address ranges (CIDRs) to allow or block traffic. Since Vercel does not provide clear CIDR ranges for its hosted projects, it becomes difficult to create firewall rules based on IP ranges. Instead, one can create custom WAF rules that do not rely on IP but instead check other aspects of the HTTP request, such as the host header or user-agent string, to identify and control traffic. This approach can serve as a kind of bypass to traditional IP-based firewall restrictions.
This method can be useful for managing access and security in environments where IP range information is unavailable or unreliable. However, it requires careful rule creation and testing to avoid unintended bypass or blocking of legitimate traffic. It's a good example of how security teams can adapt firewall strategies to the realities of modern cloud hosting platforms like Vercel.
For more insights, check out the original tweet here: https://twitter.com/oieduardorabelo/status/1960329476262473776. And don’t forget to follow @oieduardorabelo for more exciting updates in the world of cybersecurity.