WordPress标题<tag>禁止403错误（全新安装）

Question

I keep getting a Forbidden 403 error from mydomain/wp-admin/post.php.
The error only occurs when text is wrapped in a heading tag such as <h1>, error appears upon pressing save draft, publish or update.
As soon as the heading tags are removed, I am able to successfully save draft, publish or update.

Has anyone come across this issue, is this something specific to my installation or a bug?

Details:

• Wordpress version 4.7.5
• Fresh install through cPanel
• post.php file permission 644

Answer 1

It was mod_security that was somehow triggered. I contacted hosting provider and they resolved the issue. I'm guessing this occasionally happens with new site deployment.