Hello, Majid!

You could get currently active vendor by running "/usr/local/psa/admin/sbin/modsecurity_ctl -L --enabled".
In your case, I can see that "imunify360-full-apache" is already installed.
However, if you want to use Imunify360's ModSecurity rules and some other vendor is active now, you could use instructions from my previous comment.

If Imunify360's vendor is already active and upload of malicious files is still allowed, then it's unexpected behavior, please submit a ticket with our technical support at https://cloudlinux.zendesk.com (Imunify360 department) so our team can help you with the issue.

Thanks!

Hello,

What is the <YOUR_CUSTOME_RULES_NAME>? We have some *.conf files in the /etc/httpd/conf/modsecurity.d/rules/custom/ directory.
Also when we run $ imunify360-agent plesk install-vendors we got the below error:
INFO [+ 3570ms] defence360agent.subsys.panels.plesk.mod_security|Skipping vendor installationdue to conflicting vendor[s]: ['imunify360-full-apache']

Please let us know how we can configure modsecurity with your rules?

Kind Regards,

Hello!

Imunify360 could prevent upload of malicious files when Imunify360 ModSecurity rules set is enabled. As far as you using your own custom rule set, then Imunify360 rules that checking uploaded files are disabled because you could have only 1 active ruleset in Plesk. You need to disable your custom ruleset and install Imunify360's one using:

$ /usr/local/psa/admin/sbin/modsecurity_ctl --disable-all-rules --ruleset <YOUR_CUSTOM_RULES_NAME>

$ imunify360-agent plesk install-vendors

Good luck!