Abstract: An email is received that is from an email sender. From the email, the display name of the email sender, an email address of the email sender, and an email domain of the email sender, is extracted. A score is determined for the email based on at least: the extracted display name of the email sender, the extracted email address of the email sender, and the extracted email domain of the email sender, where the score indicates a probability that the email is from a legitimate sender. Message content of the email is input into multiple classifiers each corresponding to a particular message type. The message type of the email is determined based on output of the classifiers. Based on at least the determined score for the email and the determined message type of the email, a determination is made whether the email is associated with a BEC attack.

Abstract: Isolating suspicious email links is described. An email security service receives an email that includes a link that refers to an external resource. A first suspicious link determination is performed to determine whether the link is suspicious. If the link is suspicious, the link is rewritten to refer to the email security and the email is delivered to the recipient. A request from a client device is received responsive to the link being opened. A second suspicious link determination is performed to determine whether the link is suspicious. If the link is suspicious, an interstitial page is transmitted to the client device that includes an option that, when selected, causes the first link to be opened in a remote browser isolation session.

Abstract: In an embodiment, the disclosed technologies monitor electronic message traffic between a network and a recipient computer system. An embodiment includes obtaining, from an electronic message received from the network, a triple of a display name, email address, and sending domain, determining a name score for triple, and determining characteristics of the electronic message. The name score of the triple and the characteristics of the electronic message may be used to determine whether the electronic message is a spoofing attack such as a business email compromise (BEC) attack. In response to determining that the electronic message is malicious, an embodiment may cause the network to at least one of modify, delay, re-route, or block transmission of the electronic message to the recipient computer system.

Abstract: In an embodiment, the disclosed technologies monitor electronic message traffic between a network and a recipient computer system. An embodiment includes obtaining, from an electronic message received from the network, a triple of a display name, email address, and sending domain, determining a name score for triple, and determining characteristics of the electronic message. The name score of the triple and the characteristics of the electronic message may be used to determine whether the electronic message is a spoofing attack such as a business email compromise (BEC) attack. In response to determining that the electronic message is malicious, an embodiment may cause the network to at least one of modify, delay, re-route, or block transmission of the electronic message to the recipient computer system.

Abstract: In an embodiment, a computer system comprises one or more computer processors configured with a message transfer application; a message transfer/vision processing (MT/VP) interface coupled to the one or more computer processors and interposed between the message transfer application and a vision processing computer, wherein the MT/VP interface performs operations comprising: extracting risk indicator data from a message that is in transit to a recipient computer on a computer network; in response to the risk indicator data matching a message risk criterion, transmitting an image address for an image of interest coupled to the message or the image of interest to the vision processing computer; receiving, from the vision processing computer, a label that semantically describes visual content of the image of interest; using the label, querying a set of correlation data to determine a reference address that is associated with the label; in response to the image address matching the reference address, transmitting

Abstract: Techniques are described herein for detecting malicious program code stored on computer devices before the code can be executed to potentially compromise a computer network. In an embodiment, a method comprises receiving, at a computer device, a file containing instructions in a programming language; based on a syntax of the programming language, parsing the file to generate parsed information, and based on the parsed information, generating a syntax tree for the file; identifying one or more alphanumeric strings in the syntax tree, and based on the alphanumeric strings, generating a syntax string for the syntax tree; generating a hash digest by applying a piecewise hashing to the alphanumeric strings in the syntax string; determining whether the hash digest indicates that the file contains potentially malicious code; in response to determining that the hash digest indicates that the file contains the potentially malicious code, performing a responsive action.

Abstract: Systems and methods for providing an improvement to computer security relating to electronic digital messages are provided. In an embodiment, a computing device receives an electronic digital message that is sent to a receiving account. The computing device identifies a sending account associated with the electronic digital message and from which the electronic digital message was sent. The computing device obtains metadata relating to the sending account, the metadata including received message data that is related to a number of messages that have been received by the sending account. The computing device determines that the sending account satisfies a received message criteria based, at least in part, on the received message data and, in response, performs a responsive action relating to the electronic digital message.

Abstract: Systems and methods for providing an improvement to computer security relating to electronic digital messages are provided. In an embodiment, a computing device receives an electronic digital message that is sent to a receiving account. The computing device identifies a sending account associated with the electronic digital message and from which the electronic digital message was sent. The computing device obtains metadata relating to the sending account, the metadata including received message data that is related to a number of messages that have been received by the sending account. The computing device determines that the sending account satisfies a received message criteria based, at least in part, on the received message data and, in response, performs a responsive action relating to the electronic digital message.

Abstract: A computer-implemented method, comprising: detecting network messages that are emitted by a compromised computer, wherein the compromised computer comprises at least one malware item that is configured to direct unauthorized network activity toward one or more enterprise networks or enterprise computers; queuing copies of the network messages in a queue; forwarding the network messages to original destinations; determining whether the number of network messages exceeds a specified threshold associated with an attack vector; filtering by the processor, the copies that do not include one of a set of port values associated with known computer attacks; analyzing, by the processor, timing of the copies with respect to a predetermined schedule including active hours and inactive hours, detecting one or more security threats caused by the comprised computer based on the determining, filtering, and the analyzing, sending a result of the detecting to a security control computer over a communication network.

Abstract: In an embodiment, a method providing an improvement in remediating vulnerabilities in computer security comprising: receiving, using a network tap of a sensor computer that is coupled to a compromised computer, a communication packet that was sent from the compromised computer to a target computer; using the sensor computer, determining that the target computer is one of a plurality of enterprise computers; reading, at the sensor computer, a plurality of fields within a header of the communication packet; and performing a remediation measure by generating a header of an action packet, wherein the header comprises duplicates of at least some fields of the plurality of fields so as to appear to be generated by the target computer, generating a payload of the action packet, and sending the action packet comprising the generated header and the generated payload to the compromised computer.

Abstract: A data processing system comprising: a sensor computer that is coupled to and co-located with a compromised computer, the compromised computer comprising at least one malware item that is configured to direct unauthorized network activity toward one or more enterprise networks or enterprise computers, wherein the compromised computer is coupled to a firewall that is configured to control ingress of packets to the compromised computer and is logically between one or more attacker computers and the one or more enterprise networks or enterprise computers; a security control computer that is coupled to the sensor computer; one or more non-transitory data storage media in the security control computer storing security logic comprising one or more sequences of instructions which when executed cause the security control computer to perform: obtaining, from the sensor computer, detection data relating to network messages that the compromised computer emits, as the compromised computer emits the network messages; usin

Abstract: A data processing system comprising: a sensor computer that is coupled to and co-located with a compromised computer, the compromised computer comprising at least one malware item that is configured to direct unauthorized network activity toward one or more enterprise networks or enterprise computers, wherein the compromised computer is coupled to a firewall that is configured to control ingress of packets to the compromised computer and is logically between one or more attacker computers and the one or more enterprise networks or enterprise computers; a security control computer that is coupled to the sensor computer; one or more non-transitory data storage media in the security control computer storing security logic comprising one or more sequences of instructions which when executed cause the security control computer to perform: obtaining, from the sensor computer, detection data relating to network messages that the compromised computer emits, as the compromised computer emits the network messages; usin

Abstract: In an embodiment, a data processing method providing an improvement in computer security comprises selecting, from a queue identifying a plurality of web pages, a particular web page to retrieve from one of a plurality of internet sources; causing retrieving a copy of the particular web page from a particular internet source; determining a hierarchical structure of the particular web page; based upon a hierarchical structure of the particular web page and without consideration of content of the particular web page, identifying one or more features, of links in the particular web page or files referenced in the particular web page, that indicate one or more security threats; determining a reputation score for the particular web page; determining a specified remediation measure, based upon the reputation score, to remediate a security threat that is identified in the particular web page; providing the specified remediation measure to one or more of a compromised computer, a sensor computer and an enterprise com

Abstract: In an embodiment, a method providing an improvement in remediating vulnerabilities in computer security comprising: receiving, using a network tap of a sensor computer that is coupled to a compromised computer, a communication packet that was sent from the compromised computer to a target computer; using the sensor computer, determining that the target computer is one of a plurality of enterprise computers; reading, at the sensor computer, a plurality of fields within a header of the communication packet; and performing a remediation measure by generating a header of an action packet, wherein the header comprises duplicates of at least some fields of the plurality of fields so as to appear to be generated by the target computer, generating a payload of the action packet, and sending the action packet comprising the generated header and the generated payload to the compromised computer.

Abstract: A data processing system comprises a security control computer performing operations comprising: receiving, an advertising exchange network computer, advertising presentation data indicating presentations of advertisements to particular browsers that have browsed to particular websites; determining, based upon detection data, whether the particular websites are associated with network attacks or malware; in response, storing transit data specifying computers that have visited the particular web sites and using the transit data to determine a plurality of particular web pages to inspect for threats; based on a hierarchical structure of the particular web pages and without consideration of content of the particular web pages, identifying one or more features, of links in the particular web page or files referenced in the particular web pages, that indicate one or more security threats in the web pages; and determining remediation measures to remediate security threats that are identified in one of the particula

Abstract: In an embodiment, a method providing an improvement in remediating vulnerabilities in computer security comprising: receiving, using a network tap of a sensor computer that is coupled to a compromised computer, a communication packet that was sent from the compromised computer to a target computer; using the sensor computer, determining that the target computer is one of a plurality of enterprise computers; reading, at the sensor computer, a plurality of fields within a header of the communication packet; and performing a remediation measure by generating a header of an action packet, wherein the header comprises duplicates of at least some fields of the plurality of fields so as to appear to be generated by the target computer, generating a payload of the action packet, and sending the action packet comprising the generated header and the generated payload to the compromised computer.

Abstract: In an embodiment, a data processing method providing an improvement in computer security comprises selecting, from a queue identifying a plurality of web pages, a particular web page to retrieve from one of a plurality of internet sources; causing retrieving a copy of the particular web page from a particular internet source; determining a hierarchical structure of the particular web page; based upon a hierarchical structure of the particular web page and without consideration of content of the particular web page, identifying one or more features, of links in the particular web page or files referenced in the particular web page, that indicate one or more security threats; determining a reputation score for the particular web page; determining a specified remediation measure, based upon the reputation score, to remediate a security threat that is identified in the particular web page; providing the specified remediation measure to one or more of a compromised computer, a sensor computer and an enterprise com

Abstract: A data processing system comprising: a sensor computer that is coupled to and co-located with a compromised computer, the compromised computer comprising at least one malware item that is configured to direct unauthorized network activity toward one or more enterprise networks or enterprise computers, wherein the compromised computer is coupled to a firewall that is configured to control ingress of packets to the compromised computer and is logically between one or more attacker computers and the one or more enterprise networks or enterprise computers; a security control computer that is coupled to the sensor computer; one or more non-transitory data storage media in the security control computer storing security logic comprising one or more sequences of instructions which when executed cause the security control computer to perform: obtaining, from the sensor computer, detection data relating to network messages that the compromised computer emits, as the compromised computer emits the network messages; usin

Abstract: In an embodiment, a data processing method providing an improvement in computer security comprises selecting, from a queue identifying a plurality of web pages, a particular web page to retrieve from one of a plurality of internet sources; causing retrieving a copy of the particular web page from a particular internet source; determining a hierarchical structure of the particular web page; based upon a hierarchical structure of the particular web page and without consideration of content of the particular web page, identifying one or more features, of links in the particular web page or files referenced in the particular web page, that indicate one or more security threats; determining a reputation score for the particular web page; determining a specified remediation measure, based upon the reputation score, to remediate a security threat that is identified in the particular web page; providing the specified remediation measure to one or more of a compromised computer, a sensor computer and an enterprise com