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A Guide to Diagnosing and Fixing HTTP 403 Forbidden Issues


When using RadEditor to enter notes, an error occurs when underlining content. The error log indicates a server-side error with HTTP status 403 Forbidden.

Steps to Reproduce

  1. Use RadEditor to enter text.
  2. Apply the underline format to the text.
  3. Save or submit the content.


The error is caused by aggressive AWS firewall rules, specifically the CrossSiteScripting_BODY rule, which blocks the request made by RadEditor when underlining content.


To resolve this error and restore full functionality to RadEditor, follow the steps outlined below:

  1. Identify the Firewall Settings: Understand the firewall settings in your environment. In cases reported, AWS firewall rules were found to be the cause.
  2. Adjust Firewall Rules: Locate and disable the CrossSiteScripting_BODY rule or similar rules that could be incorrectly identifying RadEditor's underline function as a threat. This action should be performed with caution to ensure that disabling these rules does not inadvertently lower your site's security posture.
  3. Verify Configuration Changes: After adjusting the firewall settings, repeat the steps to reproduce the error to ensure that the issue has been resolved.
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