Webpages containing the addresses and lockbox codes of people using a dog walking app called Wag were accidentally exposed, The Wall Street Journal (WSJ) reported.

Wag Labs said it was notified last week about a glitch which leaked “certain limited personal information belonging to a small subset of Wag users,” although this did not include financial data or social security numbers.

“Given our investigation to date, we have no reason to believe this information was misused,” the company said in a statement to WSJ. The newspaper noted the data could have been used by thieves to break into users’ homes.

WSJ accessed data of around 100 customers, including more than 50 with lockbox information, before the pages were taken down, although it estimates many more people’s data may have been vulnerable.

Wag advertises the provision of a free lockbox to give dog walkers “convenient home access”. It also allows owners to track their dog’s walk with live GPS.

The app was valued at $200 million in April 2017 when it raised $45 million, bringing its total raised to about $60 million.