The vehicle was passing through the Yuksekova district of Hakkari province, which borders Iran and Iraq, when the blast occurred, the army said, adding the wounded were immediately taken to hospital.
The army initially said four of the wounded were in a serious condition, but a later statement said none of the injuries were serious.
The PKK took up arms against the Turkish state in 1984 and more than 40,000 people, mostly Kurds, have been killed in the conflict. It is designated a terrorist group by Turkey, the United States and the European Union.
A ceasefire between the Turkish state and the militants broke down in July 2015 and the southeast subsequently saw some of the worst violence since the insurgency began.