The bug was reportedly fixed after leaving cars vulnerable for several months.

Alerted by security researchers Hyundai has reportedly patched a potential vulnerability in its Blue Link connected car software.

Security firm Rapid7 says the automaker rolled out a mobile app update in early December that included a flaw that could have been used by thieves to locate, unlock and start vehicles without a physical key, according to a Reuters report.

The issue went unfixed for several months before Hyundai coders updated the company's iPhone and Android utilities. The timeframe appears to be extremely quick in the automotive industry, which is better known for its slow response to emerging cybersecurity threats.

The report does not say if the bug was patched via a change to the backend software or the mobile apps. If the latter, it is unclear if the vulnerability might still exist for users who do not automatically update their apps.

"The issue did not have a direct impact on vehicle safety," Hyundai said in a statement. "Hyundai is not aware of any customers being impacted by this potential vulnerability."