Researcher Reveals New Techniques to Bypass Cloudflare's Firewall and DDoS Protection
Oct 03, 2023
Server Security / Firewall
Firewall and distributed denial-of-service (DDoS) attack prevention mechanisms in Cloudflare can be circumvented by exploiting gaps in cross-tenant security controls, defeating the very purpose of these safeguards, it has emerged. "Attackers can utilize their own Cloudflare accounts to abuse the per-design trust-relationship between Cloudflare and the customers' websites, rendering the protection mechanism ineffective," Certitude researcher Stefan Proksch said in a report published last week. The problem, per the Austrian consulting firm, is the result of shared infrastructure available to all tenants within Cloudflare, regardless of whether they are legitimate or otherwise, thereby making it easy for malicious actors to abuse the implicit trust associated with the service and defeat the guardrails. The first issue stems from opting for a shared Cloudflare certificate to authenticate HTTP(S) requests between the service's reverse proxies and the customer's o