SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6 pl2): Invalid SQL: select * from bb1_attachments where postid IN()
mysql error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')' at line 1
mysql error number: 1064
mysql version: 5.5.62-0ubuntu0.14.04.1
php version: 5.5.9-1ubuntu4.14
Date: 26.04.2024 @ 15:40
Script: /pdf_thread,threadid-18321,sid-46b7b99ec580638bcdbfb2fb92f2409b.html
Referer: