DescriptionFraunhofer HHI VVdeC before 3.2.1 contains a heap use-after-free vulnerability in DecLibRecon::createSubPicRefBufs because decompressPicture clears m_subPicExtTasks without waiting for pending tasks. Attackers can supply a crafted multi-subpicture VVC bitstream to decoders using two or more threads, causing heap memory corruption or a decoder crash.