Turns out, iPhone's personal assistant Siri has loose lips.

Turns out, iPhone's personal assistant Siri has loose lips. (KTLA-TV)

LOS ANGELES (KTLA) -- The voice-control app called "Siri" is driving sales of Apple's latest iPhone, but some people who are concerned about their privacy say Siri is a little scary.

Eight months after Apple launched it's voice-activated personal assistant on the iPhone4S, it's become very popular.

But the American Civil Liberties Union (ACLU) now warns that there's nothing private about your relationship with Siri. As it turns out, she has loose lips!

"You never know who else is going to be in on the conversation," Los Angeles Times business columnist David Lazarus said.

According to Lazarus, Apple collects what you tell Siri, including your most personal questions.

Apple's iPhone software license agreement includes the following: "By using Siri, you agree and consent to Apple's and its subsidiaries' and agents' transmission, collection, maintenance, processing and use of this information, including your voice input and User Data."

"Apple says they record this so they can get the information back into their system and come up with a print-translation for the screen of your iPhone," Lazarus explained.

"The danger is, well, you never know what Siri is going to pick up," he added.

That's why IBM announced this week that it has banned Siri from its offices, just in case she picks up potential corporate secrets.

While most use Siri for text messaging or to find restaurants, just know that the next time you ask a question, Siri isn't the only one listening.

So how long does Apple keep all of your personal information when you use Siri? And who sees it?

The company is not giving any details.