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Email Revalidation Required - System Login Changes Coming
Cloudflare's Automated Tools
Go to Security >> Settings. There are various tools here, the one you are most interested in is "Bot Fight Mode". This will automatically block some of the most aggressive bot traffic Cloudflare has identified as malicious. Optionally, you can also enable some of the AI blocking tools.
Cloudflare Custom Rules
Go to Security >> Security Rules >> Create new Rule >> New Custom Rule. CF has an easy-to-use GUI. With the free plan, you get 5 rules. Each rule can have multiple conditions but only one action. Rules are fired in order so make sure the top rules do not interfere with subsequent rules. The following actions can be applied:
Skip - This will skip further rules based on whatever you select under WAF components to skip
Block - The request is blocked
Managed Challenge - Cloudflare will choose what challenge to issue.
Interactive Challenge - CAPTCHA that requires user interaction
JSChallenge - The "Checking your browser...." page that requires no user interaction.
Rule 1 will be used for whatever you want to allow through and skip the rest of the rules. CF maintains a list of known bots that adhere to robots.txt so you can add that if you are using robots.txt. RSS readers cannot pass the Cloudflare check, that is something else you might want to allow through if you have feeds enabled.
Field: Known Bots Operator: Equals Value: <checked>
OR
Field: URI Full Operator: Wildcard Value: https://example.com/forum/feeds/*
Action: Skip All Remaining Custom Rules
Rule 2 will be used for what you want to outright block. You can block using a variety of criteria like ASN, user agent, country, continent and many others. For this example we are blocking the "country" T1 which is used for the Tor network and the continent of Antarctica. These are just examples, phpBB harbors no ill will toward TOR or penguins :).
Field: Country Operator: Equals Value: Tor
OR
Field: Continent Operator: Equals Value: Antarctica
Action: Block
Rule 3 are phpBB specific rules for phpBB's registration page to help stop spammers from registering and brute force attacks for logins. phpBB has it's own brute force detection but for the convenience of users it's not that strict.
Field: URI query string Operator: Contains Value: mode=register
OR
Field: URI query string Operator: Contains Value: mode=login
Action: Managed Challenge
Rule 4 adds a rule for problematic countries or other conditions you want to elevate the Challenge. For action issue an Interactive Challenge. The Interactive Challenge requires the user to perform some action on screen, usually a check box. In the following example it's issued to India and China.
Field: Country Operator: Equals Value: China
OR
Field: Country Operator: Equals Value: India
Action: Interactive Challenge
Rule 5 allows you to whitelist countries and deploy a blanket policy for the rest of the world. For the action, use the JSChallenge, which is the brief "Checking your browser..." page. Countries listed here will not be challenged, add countries where you expect the bulk of your traffic to come from. It's important to note you need to use the "Does not equal" operator with AND. In the following example the US, Canada and the UK are whitelisted.
Field: Country Operator: Does not equal Value: United States
AND
Field: Country Operator: Does not equal Value: United Kingdom
AND
Field: Country Operator: Does not equal Value: Canada
Action: Interactive Challenge
Field: Known Bots Operator: Does not equal Value: <checked>
AND
Field: URI Full Operator: Wildcard Value: https://example.com/forum/feeds/*
AND
Field: Country Operator: Does not equal Value: United States
AND
Field: Country Operator: Does not equal Value: United Kingdom
AND
Field: Country Operator: Does not equal Value: Canada
Action: JSChallenge
ASN equals Amazon's
AND
user agent does not equal Duckduckgo
OR
some other condition
Pass codes: Login will use "email me a passcode code" format to login.
that they charge money in a crowdsourcing way to pay the fees (it's dying anyway).
Tangor: That's sometimes the result. Can also be the start of a better future.
My browser is Firefox, running under Linux, and I think it deletes all the cookies at the end of each session. And I am not sure that I have javascript on this machine. Have to check on that.
[edited by: mcneely at 6:40 pm (utc) on Sep 6, 2025]