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Cloudflare and malicious bots, score, challenge, origin off the internet

Opselis

Cloudflare Security Analytics, bot score, WAF and request log

Credential stuffing, cart scanning and price scraping. Bot score, JS challenge and a WAF rule, before traffic reaches the store. Origin without a public address, and a playbook that says when to raise the threshold.

A bot does not look like an SQL attack. Often it is a clean GET on /login, /cart or /api/products, repeated from many IPs. In the application log you see a jump in 4xx. In Cloudflare you see the bot score, JA3 and whether the edge issued a JS challenge or passed the request to origin.

We start with a map of paths: login, cart, search, payment webhooks. Verified bots (search, monitoring) stay on allow. Traffic with a low bot score gets a JS challenge or a block. Origin has no public address. DNS and TLS terminate at the edge.

A rule without context breaks checkout. That is why we look at sampled logs, not only the chart. If the challenge catches real customers behind a corporate proxy, we narrow the condition: path, ASN, fingerprint, not the whole hostname.

The outcome can be billed: fewer attempts on /login, the same cart response time, no surprises at the payment gateway. On-call gets a playbook for when to raise the threshold, and when to leave the challenge.