Security experts interviewed by ITV London have given the green light to the Rightmove site after it was apparently being used in a scam targeting renters in the capital.
ITV London claims that some users of the site who had been checking London rental properties had received emails claiming to be from a landlord saying an ideal property was still available.
But the recipients were then told they could only view the property with "an agent from Airbnb" and only after paying a substantial deposit.
ITV says many of the victims claim they got this e-mail after searching on Rightmove although security experts say they have checked the site and found nothing wrong.
Landlord bodies have recently opened discussion with online classified advertisement website Gumtree over scams involving fake landlords placing ads, although the Rightmove-based scam appears more sophisticated.
Sam Mitchell, head of lettings at Rightmove, says users of the site should be wary if they receive an email in connection with a property other than one they have already enquired about.
He adds: "Do not hand over money without meeting the person first. It is much safer to stick to using accredited letting agents in your area, many of whom will be listed on our site. You are much more vulnerable when renting privately with landlords who have not been accredited. If you suspect fraudulent activity after using our site, contact us immediately at email@example.com."