Timescale pgvectorscale before 0.9.1 contains a type confusion vulnerability that allows low-privileged database users to corrupt memory by shadowing pgvector's vector type or operators. Attackers with CREATE privilege on the vectorscale schema can pre-create shadow objects, then build and query DiskANN indexes over crafted values to cause out-of-bounds reads and writes, disclosing memory, crashing the server, or escalating privileges.