I've found the following PHP errors repeated in my wp-admin error log. They seem to correspond with when I try to use the Ultimate Security Checker files analysis scan, and it fails showing the following message:
"An error occurred. Please try again later."
PHP Warning: Invalid argument supplied for foreach() in /***/***/***/***/plugins/ultimate-security-checker/wp-ultimate-security.php on line 709
PHP Fatal error: Cannot use string offset as an array in /***/***/***/***/plugins/ultimate-security-checker/securitycheck.class.php on line 1007