Observed Signal · Apr 15, 2026 · Security Advisory · Source: DEV Community · Impact: 2/5 · Sentiment: Negative
DDoS Attacks Bypass Cloudflare Using 2CAPCH
A technical blog post explains how attackers can bypass Cloudflare protections and execute distributed denial-of-service (DDoS) attacks. The author describes a common technique called "2CAPCH" (a Cloudflare bypass) combined with threaded request floods or DDoS tools; this approach aims to evade Cloudflare’s interception and reveal a site’s real IP, exposing the origin server to direct attack. The piece notes that without such a bypass Cloudflare typically blocks attacks, and lists mitigation steps site operators can take: enable Cloudflare’s "Under Attack Mode", apply request rate limits, enable Browser Integrity Check, and use the Managed Challenge service. The article is presented as an educational overview rather than a formal incident report.
Highlights a practical bypass technique that can expose origin servers and disrupt websites (including publishers and ad-serving infrastructure); useful for security and ops teams but not industry‑shifting.
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Key Takeaways & Evidence Grounding
- Cloudflare provides protection services against DDoS and other web attacks.
- Attackers use a technique referred to in the post as "2CAPCH" to bypass Cloudflare protections and obtain a site's real IP.
- The bypass is combined with threading and high-request DDoS tools to attack origin servers directly.
- Recommended mitigations include enabling "Under Attack Mode", setting request limits, enabling Browser Integrity Check, and using Cloudflare's Managed Challenge.
Connected Companies & Entities
1 Entity mappedOntology Mapping & Concepts
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