Federal investigators purchased counterfeit popular products, including cosmetics and electronics, on some of the biggest and best-known e-commerce websites, according to a new report. The findings highlight new challenges for U.S. agencies and businesses in protecting consumers from potentially dangerous goods. The investigators purchased a total of 47 products from third-party sellers hosted on five major e-commerce websites: Amazon, Walmart, eBay, Sears Marketplace and Newegg. Of those, 20 were determined to be counterfeit by the companies holding the products’ intellectual property rights, the Government Accountability Office, Congress’ nonpartisan investigative division, said in a report set to be released Tuesday. The products purchased included Urban Decay cosmetics, Yeti travel mugs, UL-certified phone chargers and Nike Air Jordan shoes. All 13 Urban Decay cosmetics purchased across the five e-commerce websites were determined to be counterfeit, as were 6 of 9 Yeti mugs and 1 of 10 UL-certified phone chargers, commonly used by iPhone users.