Solved Strange problem with specific text in post

Hi to all,

I have latest Joomla / Kunena installed.

I would like to ask you about a strange problem which happens now but and in the past with older versions of joomla / kunena.

When I write a post that contains specific text e.g. syntax of commands in ms-dos or the changelog of Joomla etc, post doesn't publish and I receive the error message "Forbidden - You don't have permission to access /forum on this server."

If I delete some lines and testing to post, after some deletion and some tries it post it.

For example, if I try to post the changelog of Joomla 3.8.6 which is below :


What's in Joomla 3.8.6?
Joomla 3.8.6 addresses one security vulnerability and several bugs, including:
Security Issues Fixed
Low Priority - Core - SQLi vulnerability in User Notes (affecting Joomla 3.5.0 through 3.8.5) More information »
Bug fixes and Improvements
Various session management improvements #19548, #19687
Multilingual: Associated categories should display only when published #19551
Improve performance of the com_content category view with filter by tags #19284
[com_fields] Fields are not copied when batch duplicating an article #16958
Pass the configuration tmp_path to the archive package for extension installations #19608
Hide global configuration and system information from non super users #19697
Language overrides do not find plugin language files when files are in the plugin language folder #19740
reCAPTCHA V1 - Discontinued #19648
Delete existing user_keys, if password is changed #17827
PHP 7.2 compatibility fixes



I receive immediately the message "Forbidden - You don't have permission to access /forum on this server." and I cannot post it.

Also another strange thing is that some users in my forum they have posted similar posts with similar words (e.g. "copy c:\command.com A:" or words from changelogs that contains similar words like PHP, vulnerabilities, [com_fields] etc) and they post it with no problem!

Is this has to do with a setting or my server that have some security checks and thinks that this is malicious code?

Thanks!

Any idea?

Hi again,
I haven't solved the problem yet and some users also email me that they had the same issue with some post with text and words similar to code / php/ logs etc and they cannot publish their post because they also receive the same message ""Forbidden - You don't have permission to access /forum on this server." If they post other post with other words not containing changelogs etc the post published OK.

So to know if there is a possibility to be kunena issue or server issue so to call my hosting company, from kunena is there a chance to be a setting in configuration to cause this problem (Bad words or security filter for example) and to doesn't allow to be posted these specific text?

As I write above, even the changelog of Joomla cannot be posted in my forum - probably some filter thinks its something malicious from the words of the text......... here in kunena.org forum the changelog posted ok.

Can anyone suggest me something?

Thanks

Kunena has not a default badwords integration, looks like your input from the messages are blocked by rsfirewall? or other security plugin.

Maybe you have enabled the security module for php.

Hi, I found the cause of the problem.

Just to let you know, the problem was caused by the firewall of my hosting provider (Mod_security), so I'm trying with them to solve it.

Thanks.