"The travellers found themselves trapped in the heart of a hostile environment where extreme temperatures and lack of supply points make survival extremely difficult," said a statement from the Agadez governor.
Only two survived, trekking across the desert to Assamaka, where they alerted authorities.
The lorry had departed from the Malian town of Telhandek but veered away from its intended route, the governor's statement said.
For several days, the driver and passengers made repeated attempts to repair the vehicle, but their efforts ultimately proved unsuccessful.
Deprived of water and unable to repair the vehicle despite the efforts of the driver, his apprentice and passengers, travellers found themselves trapped in the heart of a hostile environment," the statement added.
"Dozens of lifeless bodies were found under the immobile truck and in its surroundings," it said.
The victims were buried in mass graves by the rescue team dispatched to the area by local authorities.
