controllers/member/Api.php in dayrui FineCms 5.2.0 has SQL Injection: a request with s=member,c=api,m=checktitle, and the parameter 'module' with a SQL statement, lacks effective filtering.
v5/config/system.php in dayrui FineCms 5.2.0 has a default SYS_KEY value and does not require key regeneration for each installation, which allows remote attackers to upload arbitrary .php files via a member api swfupload action to index.php.