Scarlett Johansson Dating N.Y.C. Ad Exec: Source

By Alexis Chiu and Dahvi Shira

Tuesday January 31, 2012 05:30 PM EST

Scarlett Johansson Dating N.Y.C. Ad Exec: Source | Scarlett Johansson

Nate and Scarlett Johansson

Elder Ordonez/INF

Scarlett Johansson's rep has brushed off recent rumors that she's dating Kieran Culkin or Justin Bartha – but a source tells PEOPLE that the recent divorcée is now romancing someone for real.

The We Bought a Zoo star, 27, is seeing an New York City-based advertising executive named Nate Naylor, a pal of the pair confirms.

"They've been dating for five months," the source adds.

The actress's rep has no comment this time, but recent photos show the happy couple strolling the Big Apple streets, holding hands.

Meanwhile, the home that Johansson and ex-hubby Ryan Reynolds shared before they split a little more than a year ago, is back on the market.

Located in the posh hills of L.A.'s Los Feliz community, the four-bedroom, three-bathroom estate is on sale for $3,650,000.

• Reporting by MELODY CHIU