Network security is becoming increasingly important as the information age continues to unfold. Network threats may take a variety of forms (e.g., unauthorized requests or data transfers, viruses, malware, large volumes of network traffic designed to overwhelm network resources, and the like). Many organizations subscribe to network-threat services that periodically provide information associated with network threats, for example, reports that include listings of network-threat indicators (e.g., network addresses, uniform resources identifiers (URIs), and the like). The information provided by such services may be utilized by organizations to identify network threats. For example, logs generated by the organization's network devices may be reviewed for data corresponding to the network-threat indicators provided by such services. But because the logs are generated based on the traffic processed by the network devices without regard to the network-threat indicators, this process is often tedious and time consuming and is exacerbated by the continuously evolving nature of potential threats. Accordingly, there is a need for rule-based network-threat detection.