I have seen a curl error reported when updating plugins on a WordPress website. The cause has been memory related.
A typical observed error when updating WordPress plugins is
Download failed. cURL error 77: Problem with the SSL CA cert (path? access rights?)
The version of php in use was 5.6. An update to the newer version 7.2 was trialled without success.
Plugins were deactivated to determine whether one or more of these was the issue. Care was taken to check whether the problem moved by re-enabling a plugin and disabling another. The problem transferred showing it not to be a specific plugin.
It was determined that the issue was memory allocation aggravated by the number of active plugins.
The memory allocated to a website is a part of the server configuration, limited by the physical installed memory and the allocation across the sites hosted on the server.
Depending upon the memory limit you may need to take actions to reduce your requirements. And if you are lucky the hosting company will be able to raise your memory limit. It’s possible that you may have to move from shared hosting to a virtual server, for example.
Have you duplication in the plugins which are installed? For example do you have more than one form plugin? If so then chose which you prefer to use and delete the others. The fewer plugins installed the lower your security target.
