In this short paper, we take a first step towards empirically assessing Internet-wide malicious activities generated from and targeted towards Internet-scale business sectors (i.e., financial, health, education, etc.) and critical infrastructure (i.e., utilities, manufacturing, government, etc.). Facilitated by an innovative and a collaborative large-scale effort, we have conducted discussions with numerous Internet entities to obtain rare and private information related to allocated IP blocks pertaining to the aforementioned sectors and critical infrastructure. To this end, we employ such information to attribute Internet-scale maliciousness to such sectors and realms, in an attempt to provide an in-depth analysis of the global cyber situational posture. We draw upon close to 16.8 TB of darknet data to infer probing activities (typically generated by malicious/infected hosts) and DDoS backscatter, from which we distill IP addresses of victims. By executing week-long measurements, we observed an alarming number of more than 11,000 probing machines and 300 DDoS attack victims hosted by critical sectors. We also generate rare insights related to the maliciousness of various business sectors, including financial, which typically do not report their hosted and targeted illicit activities for reputation-preservation purposes. While we treat the obtained results with strict confidence due to obvious sensitivity reasons, we postulate that such generated cyber threat intelligence could be shared with sector/critical infrastructure operators, backbone networks and Internet service providers to contribute to the overall threat remediation objective.