Slack recently entered a quiet period ahead of its public market debut, which is expected later this year. Meanwhile, many corporate executives would like a little more quietness on the Slack messaging app, where employees are prone to saying way too much.
More than 10 million people use Slack every day, mostly to communicate with co-workers. The app has gained so much popularity in the five-plus years since its launch that private investors value the company at over $7 billion.
But executives who spoke with CNBC about employee use of the app fear that the freely exchanged — and often sensitive — information could easily find its way into more public forums.
"I love my people, but they never shut up on Slack," said the CEO of a security company who asked not to be named so he could speak openly about his concerns. "It's very good for productivity, but the problem is we're working on security, so we have to be careful about what we say."
Employees communicate on Slack using "channels" to focus conversations on various topics specific to different departments. It followed corporate chat tools from Microsoft, Google and Cisco as well as a plethora of start-ups, but none gained Slack's level of adoption or had so much success in pulling workers away from email and into messaging groups.