Changelog

Cloudflare Email security now lets administrators write their own content-based blocking rules. A new Blocked content area under Policies & rules lets you define a plaintext string or a regular expression, choose whether to scan the message subject, body, or both, and automatically block any message that matches.

• Create rules using either plaintext matches or regular expressions — useful for blocking targeted phishing campaigns, known-bad phrases, or content patterns unique to your organization.
• Choose the search location for each rule: subject, body, or subject and body.
• Use the built-in regular expression checker to validate your pattern against sample text before saving, so you can confirm the rule matches what you expect and avoid false positives.
• Matching messages are marked with a malicious disposition and prevented from reaching users' inboxes.

Blocked content rules currently only support the block action.

This feature is available for the following Email security packages:

• Enterprise
• Enterprise + PhishGuard

To get started, refer to Blocked content.