Syrian rebels are seen loading and firing the old artillery gun.
Bild reports that this particular type of howitzer, the 10.5cm leFH18, was one of the most common artillery guns used by the Wehrmacht during the war.
It was designed by Rheinmetall at the end of the 1920s, and entered service with the Wehrmacht in 1935. From 1935-45 over 10,000 were produced.
They can fire 14kg artillery shells a distance of ten kilometers.
The howitzer was used all over Europe during the war, but it remains a mystery how the rebels got their hands on one in Syria.
"The Syrian army had a few in service. The rebels probably stole it from the army or maybe a museum," expert Nic R. Jensen Jones told Bild.
"When fighters only have limited access to modern weapons, it's quite common that they resort to using older models," he continued.
The civil war in Syria has been raging since the original unrest as part of the Arab Spring in 2011, and a wide variety of weaponry has been used.
Examples include the Karabiner 98k, the standard service rifle of the Wehrmacht, as well as others from Britain, the USA, France and Russia.
Syrian rebels sparked particular interest three years ago when they revealed they had 5,000 StG 44s, another German weapon from the Second World War, which is considered to be the first modern assault rifle.
"Either they were stolen by victorious Soviet troops and then given or sold to Syria, or delivered to Syria from the GDR, who used the StG 44 up until the early 1980s," Jenzen-Jones suggested.