Disallow new plugin and theme installs, but allow updates

Hi, I was wondering whether there is a way to block new theme and plugin installs and uploads (for everyone, even admins) from the dashboard, but allow update checking and installation. I was looking to harden my WordPress installation in case of a admin area intrusion (so the hacker couldn’t just install a WP file manager plugin and download, modify files to his heart’s content), and only found the DISALLOW_FILE_MODS constant, which blocks both new plugin installs, and updates. Am i missing something, or is there no way to block new plugin and theme install with a constant?

• This topic was modified 3 years, 3 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic