A vulnerability has been found in GibbonEdu Gibbon up to 30.0.01. The affected element is the function makeBlock of the file modules/Planner/units_add_blockAjax.php of the component Unit Planner. The manipulation of the argument gibbonUnitBlockID/mode leads to missing authentication. The attack is possible to be carried out remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 31.0.00 is sufficient to fix this issue. The identifier of the patch is 07e719368eae8dfb4e22e19424ceab6074164ebc. It is recommended to upgrade the affected component.