Oil drilling and fracking giant Halliburton said it has shut down some of its internal systems following a cyberattack earlier this week. In a brief statement filed with government regulators on Thursday, Halliburton said it became aware of unauthorized access to its systems on Wednesday and responded by “proactively taking certain systems offline.” The company said it is “working to identify any effects of the incident.” Halliburton, which has close to 48,000 employees in dozens of countries per company f ...