Chinese authorities rapped Walmart for allegedly violating cybersecurity laws, local media reported, the latest trouble for the U.S. retailer that is already a target of accusations in the country for supposedly stopping sales of products from Xinjiang. Police in the southern Chinese city of Shenzhen discovered 19 "vulnerabilities" in Walmart's network system in late November and accused it of being slow to fix the loopholes, the China Quality News, backed by the country's market regulator, reported on Wednesday. Walmart was ordered to make rectifications, the report said, without mentioning any fines or details of the vulnerabilities. The retail giant and…