Security level
Cloudflare's Security Level uses the threat score (IP reputation) to decide whether to present a challenge to the visitor. Once the visitor enters the correct challenge, they receive the appropriate website resources.
The threat score measures IP reputation across Cloudflare services. This score is calculated based on Project Honeypot ↗, external public IP information, as well as internal threat intelligence from our WAF managed rules and DDoS.
The threat score of a request has a value from 0 to 100, where 0 indicates low risk. Values above 10 may represent spammers or bots, and values above 40 identify bad actors on the Internet.
Security levels are based on the threat score (except Off and I'm Under Attack!). You can adjust the security level to challenge incoming requests based on the threat they pose.
The available security levels are the following:
| Security Level | Description |
|---|---|
| Off (Enterprise customers only) | Does not challenge IP addresses. |
| Essentially off | Only challenges IP addresses with the worst reputation. |
| Low | Challenges only threatening visitors. |
| Medium | Challenges both threatening and moderately threatening visitors. |
| High | Challenges all visitors that exhibited threatening behavior within the last 14 days. |
| I'm Under Attack! | Only for use if your website is currently under a DDoS attack. |
Selecting a higher Security Level value means that even requests with a lower risk (that is, with a low threat score) will be challenged. Selecting a lower Security Level value means that only requests posing a higher risk (that is, with a high threat score) will be challenged.
Security levels from Essentially off to High will challenge the visitor using a Managed Challenge. When you select I'm Under Attack!, which enables I'm Under Attack mode, Cloudflare will present a JS challenge page.