At the SXSW (South by Southwest) annual interactive technology and music festival in Austin, Salmon said an unnamed source told him that the 24-hour cable news network said an announcement is expected for Tuesday regarding the deal, which will be worth "upwards of $200 million."
CNN, a division of Time Warner, and Mashable didn't immediately return requests for comment.
Mashable calls itself "the largest independent online news site dedicated to covering digital culture, social media and technology" with more than 20 million unique monthly visitors. Headquartered in New York City, the company was founded in 2005.
Salmon compared the reported acquisition to AOL's purchase of Tech Crunch in September 2010. He said that acquisition, estimated to be $25 to $40 million, "ended in tears." Arianna Huffington, the president and editor-in-chief of AOL Huffington Post Media Group, reportedly ousted TechCrunch editor and founder Michael Arrington a year later when he announced he was starting a venture fund.