The phrase "sophisticated hackers" refers to highly skilled and advanced individuals who are capable of overcoming complex cybersecurity measures and conducting sophisticated cyber attacks. Full definition
On the other hand, some of the more sophisticated hackers can afford copy editors too. (lawyerist.com)
At times lost in translation is the fact that many security vulnerabilities can be exploited by only the most sophisticated hackers who have the time, will and financial incentive to do this. (scientificamerican.com)