AmandaEve on "[Plugin: Limit Post Add-On] Security issues?"

I'm getting some errors concerning Malware from your plugin:

MalwareSecurity warning in the URL: http://www.acrc.ca
*Site error detected. Details: web.php.notice.undefined-index <b>Notice</b>: Undefined index: p in <b>/home/acrc/acrc.ca/wp-content/plugins/limit-post-add-on/limit-post.php</b> on line <b>43</b>

Security warning in the URL: http://acrc.ca/
*Site error detected. Details: web.php.notice.undefined-index <b>Notice</b>: Undefined index: p in <b>/.../plugins/limit-post-add-on/limit-post.php</b> on line <b>43</b>

Security warning in the URL: http://www.acrc.ca/about/health-and-welfare/
*Site error detected. Details: web.php.notice.undefined-index <b>Notice</b>: Undefined index: p in <b>/.../plugins/limit-post-add-on/limit-post.php</b> on line <b>43</b>

Security warning in the URL (for Google's UA): http://www.acrc.ca
*Site error detected. Details: web.php.notice.undefined-index <b>Notice</b>: Undefined index: p in <b>.../plugins/limit-post-add-on/limit-post.php</b> on line <b>43</b>

I'm wondering if there's anything I can do to fix this?

https://wordpress.org/plugins/limit-post-add-on/