Security researchers with US cybersecurity firm Symantec say they have discovered a “highly sophisticated” Chinese hacking tool that has been able to escape public attention for more than a decade. The discovery was shared with the US government in recent months, who have shared the information with foreign partners, a US official said. Symantec, a division of chipmaker Broadcom, published its research about the tool – which it calls Daxin – on Monday. “It’s something we haven’t seen before,” said Clayton Romans, associate director with the US Cybersecurity Infrastructure Security Agency (CISA). “This is the exact type of information we’re…