Apache error: mod_fcgid: stderr: PHP Notice: Undefined index: core

Hi team,

I have this error in my Apache error log:
[Tue Mar 22 01:19:48.349437 2016] [fcgid:warn] [pid 27800] [client 123.30.175.230:51431] mod_fcgid: stderr: PHP Notice: Undefined index: core in /home/danhgia/public_html/administrator/components/com_easysocial/includes/privacy/privacy.php on line 397
Is it acceptable?

Thanks,
Giang Anh