Fire risk Hotpoint washing machines at the centre of a safety scare were listed on eBay and Facebook Marketplace with no checks.
Two models which were part of a Whirlpool recall of more than half a million machines appeared on the sites.
A probe by charity Electrical Safety First to test the ease of placing adverts for known faulty products exposed a “shameful lack of measures”.
It listed two items for sale on eBay and Facebook Marketplace.
They were among 42 Hotpoint and Indesit models in the recall of 519,000 machines before Christmas.
Both models, which had a flawed door-locking system, could overheat.
While eBay removed the ad after three-and-a-half days and told the seller the appliance may be part of a recall, Facebook Marketplace did nothing.
Electrical Safety First, who axed the latter ad after a week, is calling for tougher safeguards.
Technical director Martyn Allen said: “Marketplaces can’t wash their hands of responsibility.”
Yesterday eBay said it did not allow sellers to list items banned because of a recall, saying: “Safety is our priority.” Watchdog Which? urged Government intervention.
A Facebook spokesperson said: “We do not allow the sale or purchase of recalled products on our platform and are in the process of improving our systems to find and remove these types of listings on Marketplace.
"When we become aware of listings or products that violate our policies, we immediately take action.”
