The privacy problems never stop coming for Facebook. According to a report in CNBC this week, marketers were able to access information from a private group for breast cancer gene carriers using a Google Chrome extension. The tool, which allowed marketers to retrieve the names of people in private groups, was subsequently shut down by Facebook.

If insurance companies discovered that these women had preexisting conditions, the companies could offer worse discriminatory coverage. Of course, it’s also a highly sensitive medical issue that most people wouldn’t want companies or anyone outside of their immediate circle of friends and family to know.

The issue came to light when one of the group’s moderators became aware of a tool that let her download the personal information of all 9,000 members. Then she reached out to a security researcher to confirm, and once he did, he submitted a report to Facebook. While Facebook responded by closing this functionality, the company denied that the problem constituted a “loophole.”

“While we recently made a change to closed groups, there was not a privacy loophole,” a company spokesperson told CNET. 

Whatever Facebook’s technical definition of a loophole is, it’s clear this was an issue that badly needed to be addressed. And if it wasn’t for eagle-eyed users, it might not have been noticed at all.