The invention relates to a composite panel (1), comprising two fibrous plies (21) and a core (3) placed in the intervening volume between the plies (21) and connected together by a solidified binding material (22), characterized in that openings (6) are made in the core (3), via at least one of its faces (31; 32), so as to exclusively receive solidified binding material (22). The invention also relates to a device and to a method for manufacturing such a composite panel. Use for inexpensively producing particularly strong composite panels, with the possibility of having a very wide range of options as regards the constituents of the core and of the fibrous plies.