Mališan (pennant number: P-901) was a CB-class midget submarine that served in the Yugoslav Navy (Serbo-Croatian: Jugoslavenska ratna mornarica; JRM) from 1953 to 1957.

Handed over to the navy of the Italian Social Republic – a wartime German puppet state – she was captured by Yugoslav ground forces in the port of Pola at the end of the war.

The submarine had been on display for almost 50 years before undergoing an extensive internal and external restoration beginning in 2008 with collaboration among the museum, Maritime Institute, the University of Zagreb and private contractors.

The Italian Regia Marina (Royal Navy) built various classes of midget submarines for harbour defence and anti-submarine warfare.

[1] Built in Milan by the Caproni company – better known as an aircraft manufacturer[2] – Mališan was laid down in 1943 as CB-20,[3] and was intended for service in the Regia Marina.

[2] The electric motor was powered by 308 batteries which were located under the control room and charged by running the diesel engine on the surface.

[5] The boat was then handed over to the navy of the Italian Social Republic (RSI)[8] – a World War II German puppet state formed in northern Italy under Benito Mussolini[9] – and the boat saw service with the 1st Submarine Group Comandante Lombardo of the Decima Flottiglia MAS (Xª MAS), a flotilla performing reconnaissance and landing saboteurs.

[12] The rails aft of the conning tower were removed,[2] and a 7.92-millimetre (0.31 in) machine gun was stored inside the boat for mounting forward if needed.

Mališan had to release air bubbles to indicate her position to the patrol boat crews, due to her small size and difficulty of detection.

[8] According to the Technical Museum, CB-26 was incomplete in 2021 and had been restored in an "inappropriate way" (neodgovarajući način),[5] and the Croatian defence and security journalist Boris Švel [hr] reported in 2013 that the interior of CB-26 was in complete disrepair.

Work started in 2008, and was focused on restoring the interior by dismantling all removable parts from the command section and the engine room.

A custom crane had to be constructed and mounted in order to extract the compressor, electric motor and other equipment weighing more than 100 kilograms (220 lb).

The restoration work was a collaboration among the Technical Museum, the Maritime Institute, the Faculty of Mechanical Engineering and Naval Architecture of the University of Zagreb, and companies Baština d.o.o.

Work on the exterior also included the restoration of the original Italian paint scheme and name instead of retaining the appearance and designation used during its Yugoslav service.