Updated: 28 September 2026 · Applies to: cPanel & WHM 138 (Jupiter theme)
ModSecurity is a web application firewall on our servers. It blocks requests that look like common attacks, such as SQL injection or malicious uploads. Now and then it also blocks a normal action, for example saving a page in your CMS, and you see a 403 Forbidden or 406 Not Acceptable error.
Turn it off for one domain
- Log in to cPanel (for example at
https://yourdomain.com:2083, or from the Ucartz client area). - Open Security › ModSecurity.
- Find the domain and switch its Status to Off.
- Repeat the action that was blocked. If it now works, ModSecurity was the cause.
Better: keep it on and ask us to adjust the rule
Switching ModSecurity off removes protection for the whole domain. Instead, switch it back on and open a support ticket with the page address, the time of the error and your IP address. We can find the exact rule in the server log and add an exception for just that part of your site.
Note: If the ModSecurity option is not in your cPanel, the server administrator manages it. Open a ticket and we will check the block for you.
Ucartz services for this topic
- KVM VPS hosting: NVMe SSD and full root access, with Free Basic Managed Support.
- Unmanaged dedicated servers: full root access and free IPMI KVM, with Free Basic Managed Support.
- Linux server management: hardening, patching, monitoring and automation for Ubuntu, Debian, RHEL and AlmaLinux.
