A security flaw has been discovered in OS4ED openSIS-Classic up to 9.3. This affects an unknown function of the file functions/CustomFieldsFnc.php of the component Student Search. The manipulation of the argument cust results in sql injection. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.