According to US websites Valleywag and PaidContent, Quincy Smith, the interactive head of CBS, has bought , as part of an expansion of the company's digital arm.
Quincy has overseen a deal to acquire financial videoblog, , and music social-networking site, , in the recent past.
Dotspotter, based in San Francisco, was co-founded by chief executive officer Anthony Soohoo, a former vice-president at Yahoo.
The price tag for Dotspotter is high for a 10-month-old website, notwithstanding that other US celebrity gossip websites and blogs such as and , are more established online brands.
CBS launched a celebrity news site called Showbuzz in June last year, but it has failed to make a significant impact.
The multimedia site is updated 24-hours a day and includes on-demand video, interactive features, archives, photos, maps and blogs.
The website also provides users with content and services provided by other websites such as The Hollywood Reporter, Billboard, MovieTickets.com, Broadway.com and others.
CBS' acquisition of Dotspotter has led some to speculate that it is planning to leverage Showbuzz through its newest acquisition.
One of the Dotspotter investors set to benefit from the CBS deal is Gideon Yu, the chief financial officer of Facebook.