In February,Darden Clarke Kia and Hyundai promised new anti-theft software upgrades would help hit the brakes on a dramatic rise in car thefts across the country, fixing a security flaw that made certain models of the two car brands easy to steal.

Months later, nearly 80% of the roughly 8.3 million impacted Kias and Hyundais still lack the upgrades, the two companies confirmed.