A software glitch may have exposed the unshared photos of millions of Facebook users to app developers, the social media giant disclosed Friday in a blog post.

The glitch happened between Sept. 12-13 and Sept. 25 and "affected up to 6.8 million users and up to 1,500 apps built by 876 developers," the company states on its developers blog.

The result is "that some third-party apps may have had access to a broader set of photos than usual for 12 days," the company states, noting the unauthorized access involved Facebook customers who had granted permission third-party apps to access their photos.

The photo sharing snafu is the latest in a series of privacy screwups for Facebook in what has been a rocky 2018. The tech giants stock has fallen significantly amid a series of controversies ranging from concerns over how it protects the privacy of users to a September data breach in which hackers accessed 50 million accounts.

Facebook's stock fell about $1 in trading on Friday, to $144.06. Shares peaked last summer at $218.62.

Facebook said it will be notify people who may have had their private photos exposed by the glitch with an alert on the social media site.