Abstract: The attack vectors for some denial-of-service cyber attacks on the Internet's Domain Name System (DNS) are bad, bogus, or unregistered domain name DNS requests to resolve domain names that are not registered in the DNS. Some other cyber attacks steal sensitive data by encoding the data in bogus domain names, or domain names otherwise not registered in the DNS, that are transferred across networks in bogus DNS requests. A DNS gatekeeper may filter in-transit packets containing DNS requests and may efficiently determine if a request's domain name is registered in the DNS. When the domain name is not registered in the DNS, the DNS gatekeeper may take one of a plurality of protective actions. The DNS gatekeeper drops requests determined not to be legitimate, which may prevent an attack.

Abstract: A packet gateway may protect TCP/IP networks by enforcing security policies on in-transit packets that are crossing network boundaries. The policies may include packet filtering rules derived from cyber threat intelligence (CTI). The rapid growth in the volume of CTI and in the size of associated CTI-derived policies, coupled with ever-increasing network link speeds and network traffic volume, may cause the costs of sufficient computational resources to be prohibitive. To efficiently process packets, a packet gateway may be provided with at least one probabilistic data structure, such as a Bloom filter, for testing packets to determine if packet data may match a packet filtering rule. Packet filtering rules may be grouped into subsets of rules, and a data structure may be provided for determining a matching subset of rules associated with a particular packet.

Abstract: A cyber threat intelligence (CTI) gateway device may receive rules for filtering TCP/IP packet communications events that are configured to cause the CTI gateway device to identify communications corresponding to indicators, signatures, and behavioral patterns of network threats. The CTI gateway device may receive packets that compose endpoint-to-endpoint communication events and, for each event, may determine that the event corresponds to criteria specified by a filtering rule. The criteria may correspond to one or more of the network threat indicators, signatures, and behavioral patterns. The CTI gateway may create a log of the threat event and forward the threat event log to a task queue managed by a cyberanalysis workflow application. Human cyberanalysts use the cyberanalysis workflow application to service the task queue by removing the task at the front of the queue, investigating the threat event, and deciding whether the event is a reportable finding that should be reported to the proper authorities.

Abstract: A packet-filtering device may receive packet-filtering rules configured to cause the packet-filtering device to identify packets corresponding to network-threat indicators. The packet-filtering device may receive packets and, for each packet, may determine that the packet corresponds to criteria specified by a packet-filtering rule. The criteria may correspond to one or more of the network-threat indicators. The packet-filtering device may apply an operator specified by the packet-filtering rule. The operator may be configured to cause the packet-filtering device to either prevent the packet from continuing toward its destination or allow the packet to continue toward its destination.

Abstract: A packet-filtering system described herein may be configured to filter packets with encrypted hostnames in accordance with one or packet-filtering rules. The packet-filtering system may resolve a plaintext hostname from ciphertext comprising an encrypted Server Name Indication (eSNI) value. The packet-filtering system may resolve the plaintext hostname using a plurality of techniques. Once the plaintext hostname is resolved, the packet-filtering system may then use the plaintext hostname to determine whether the packets are associated with one or more threat indicators. If the packet-filtering system determines that the packets are associated with one or more threat indicators, the packet-filtering system may apply a packet filtering operation associated with the packet-filtering rules to the packets.

Abstract: A threat intelligence gateway (TIG) may protect TCP/IP networks from network (e.g., Internet) threats by enforcing certain policies on in-transit packets that are crossing network boundaries. The policies may be composed of packet filtering rules with packet-matching criteria derived from cyber threat intelligence (CTI) associated with Internet threats. These CTI-derived packet-filtering rules may be created offline by policy creation and management servers, which may distribute the policies to subscribing TIGs that subsequently enforce the policies on in-transit packets. Each packet filtering rule may specify a disposition that may be applied to a matching in-transit packet, such as deny/block/drop the in-transit packet or pass/allow/forward the in-transit packet, and also may specify directives that may be applied to a matching in-transit packet, such as log, capture, spoof-tcp-rst, etc.

Abstract: A packet-filtering network appliance such as a threat intelligence gateway (TIG) protects TCP/IP networks from Internet threats by enforcing certain policies on in-transit packets that are crossing network boundaries. The policies are composed of packet filtering rules derived from cyber threat intelligence (CTI). Logs of rule-matching packets and their associated flows are sent to cyberanalysis applications located at security operations centers (SOCs) and operated by cyberanalysts. Some cyber threats/attacks, or incidents, are composed of many different flows occurring at a very high rate, which generates a flood of logs that may overwhelm computer, storage, network, and cyberanalysis resources, thereby compromising cyber defenses.

Abstract: The attack vectors for some denial-of-service cyber attacks on the Internet's Domain Name System (DNS) are bad, bogus, or unregistered domain name DNS requests to resolve domain names that are not registered in the DNS. Some other cyber attacks steal sensitive data by encoding the data in bogus domain names, or domain names otherwise not registered in the DNS, that are transferred across networks in bogus DNS requests. A DNS gatekeeper may filter in-transit packets containing DNS requests and may efficiently determine if a request's domain name is registered in the DNS. When the domain name is not registered in the DNS, the DNS gatekeeper may take one of a plurality of protective actions. The DNS gatekeeper drops requests determined not to be legitimate, which may prevent an attack.

Abstract: A cyber threat intelligence (CTI) gateway device may receive rules for filtering TCP/IP packet communications events that are configured to cause the CTI gateway device to identify communications corresponding to indicators, signatures, and behavioral patterns of network threats. The CTI gateway device may receive packets that compose endpoint-to-endpoint communication events and, for each event, may determine that the event corresponds to criteria specified by a filtering rule. The criteria may correspond to one or more of the network threat indicators, signatures, and behavioral patterns. The CTI gateway may create a log of the threat event and forward the threat event log to a task queue managed by a cyberanalysis workflow application. Human cyberanalysts use the cyberanalysis workflow application to service the task queue by removing the task at the front of the queue, investigating the threat event, and deciding whether the event is a reportable finding that should be reported to the proper authorities.

Abstract: A packet-filtering device may receive packet-filtering rules configured to cause the packet-filtering device to identify packets corresponding to network-threat indicators. The packet-filtering device may receive packets and, for each packet, may determine that the packet corresponds to criteria specified by a packet-filtering rule. The criteria may correspond to one or more of the network-threat indicators. The packet-filtering device may apply an operator specified by the packet-filtering rule. The operator may be configured to cause the packet-filtering device to either prevent the packet from continuing toward its destination or allow the packet to continue toward its destination.

Abstract: A packet-filtering system described herein may be configured to filter packets with encrypted hostnames in accordance with one or packet-filtering rules. The packet-filtering system may resolve a plaintext hostname from ciphertext comprising an encrypted Server Name Indication (eSNI) value. The packet-filtering system may resolve the plaintext hostname using a plurality of techniques. Once the plaintext hostname is resolved, the packet-filtering system may then use the plaintext hostname to determine whether the packets are associated with one or more threat indicators. If the packet-filtering system determines that the packets are associated with one or more threat indicators, the packet-filtering system may apply a packet filtering operation associated with the packet-filtering rules to the packets.

Abstract: A packet-filtering system described herein may be configured to filter packets with encrypted hostnames in accordance with one or packet-filtering rules. The packet-filtering system may resolve a plaintext hostname from ciphertext comprising an encrypted Server Name Indication (eSNI) value. The packet-filtering system may resolve the plaintext hostname using a plurality of techniques. Once the plaintext hostname is resolved, the packet-filtering system may then use the plaintext hostname to determine whether the packets are associated with one or more threat indicators. If the packet-filtering system determines that the packets are associated with one or more threat indicators, the packet-filtering system may apply a packet filtering operation associated with the packet-filtering rules to the packets.

Abstract: A threat intelligence gateway (TIG) may protect TCP/IP networks from network (e.g., Internet) threats by enforcing certain policies on in-transit packets that are crossing network boundaries. The policies may be composed of packet filtering rules with packet-matching criteria derived from cyber threat intelligence (CTI) associated with Internet threats. These CTI-derived packet-filtering rules may be created offline by policy creation and management servers, which may distribute the policies to subscribing TIGs that subsequently enforce the policies on in-transit packets. Each packet filtering rule may specify a disposition that may be applied to a matching in-transit packet, such as deny/block/drop the in-transit packet or pass/allow/forward the in-transit packet, and also may specify directives that may be applied to a matching in-transit packet, such as log, capture, spoof-tcp-rst, etc.

Abstract: A cyber threat intelligence (CTI) gateway device may receive rules for filtering TCP/IP packet communications events that are configured to cause the CTI gateway device to identify communications corresponding to indicators, signatures, and behavioral patterns of network threats. The CTI gateway device may receive packets that compose endpoint-to-endpoint communication events and, for each event, may determine that the event corresponds to criteria specified by a filtering rule. The criteria may correspond to one or more of the network threat indicators, signatures, and behavioral patterns. The CTI gateway may create a log of the threat event and forward the threat event log to a task queue managed by a cyberanalysis workflow application. Human cyberanalysts use the cyberanalysis workflow application to service the task queue by removing the task at the front of the queue, investigating the threat event, and deciding whether the event is a reportable finding that should be reported to the proper authorities.

Abstract: A packet-filtering device may receive packet-filtering rules configured to cause the packet-filtering device to identify packets corresponding to network-threat indicators. The packet-filtering device may receive packets and, for each packet, may determine that the packet corresponds to criteria specified by a packet-filtering rule. The criteria may correspond to one or more of the network-threat indicators. The packet-filtering device may apply an operator specified by the packet-filtering rule. The operator may be configured to cause the packet-filtering device to either prevent the packet from continuing toward its destination or allow the packet to continue toward its destination.

Abstract: A packet-filtering device may receive packet-filtering rules configured to cause the packet-filtering device to identify packets corresponding to network-threat indicators. The packet-filtering device may receive packets and, for each packet, may determine that the packet corresponds to criteria specified by a packet-filtering rule. The criteria may correspond to one or more of the network-threat indicators. The packet-filtering device may apply an operator specified by the packet-filtering rule. The operator may be configured to cause the packet-filtering device to either prevent the packet from continuing toward its destination or allow the packet to continue toward its destination.

Abstract: A packet-filtering network appliance such as a threat intelligence gateway (TIG) protects TCP/IP networks from Internet threats by enforcing certain policies on in-transit packets that are crossing network boundaries. The policies are composed of packet filtering rules derived from cyber threat intelligence (CTI). Logs of rule-matching packets and their associated flows are sent to cyberanalysis applications located at security operations centers (SOCs) and operated by cyberanalysts. Some cyber threats/attacks, or incidents, are composed of many different flows occurring at a very high rate, which generates a flood of logs that may overwhelm computer, storage, network, and cyberanalysis resources, thereby compromising cyber defenses.

Abstract: A packet-filtering device may receive packet-filtering rules configured to cause the packet-filtering device to identify packets corresponding to network-threat indicators. The packet-filtering device may receive packets and, for each packet, may determine that the packet corresponds to criteria specified by a packet-filtering rule. The criteria may correspond to one or more of the network-threat indicators. The packet-filtering device may apply an operator specified by the packet-filtering rule. The operator may be configured to cause the packet-filtering device to either prevent the packet from continuing toward its destination or allow the packet to continue toward its destination.

Abstract: A threat intelligence gateway (TIG) may protect TCP/IP networks from network (e.g., Internet) threats by enforcing certain policies on in-transit packets that are crossing network boundaries. The policies may be composed of packet filtering rules with packet-matching criteria derived from cyber threat intelligence (CTI) associated with Internet threats. These CTI-derived packet-filtering rules may be created offline by policy creation and management servers, which may distribute the policies to subscribing TIGs that subsequently enforce the policies on in-transit packets. Each packet filtering rule may specify a disposition that may be applied to a matching in-transit packet, such as deny/block/drop the in-transit packet or pass/allow/forward the in-transit packet, and also may specify directives that may be applied to a matching in-transit packet, such as log, capture, spoof-tcp-rst, etc.

Abstract: A packet-filtering system described herein may be configured to filter packets with encrypted hostnames in accordance with one or packet-filtering rules. The packet-filtering system may resolve a plaintext hostname from ciphertext comprising an encrypted Server Name Indication (eSNI) value. The packet-filtering system may resolve the plaintext hostname using a plurality of techniques. Once the plaintext hostname is resolved, the packet-filtering system may then use the plaintext hostname to determine whether the packets are associated with one or more threat indicators. If the packet-filtering system determines that the packets are associated with one or more threat indicators, the packet-filtering system may apply a packet filtering operation associated with the packet-filtering rules to the packets.