This system is directed to a computerized system for extracting, analyzing, aggregating, and storing senders' behavior including temporal patterns of messages, volume, frequency, velocity, and acceleration or declaration of messages.
The use of electronic messages, especially email, is prevalent in today's society. It is estimated that billions of emails are sent per day. Email is being used for several purposes including personal communications, business communications, marketing, advertising, multi-party communications, collaboration, transmitting attachments, documents, or any other informational interactions, as well as many other uses. With increased use there also comes an increased risk.
One such risk is that an electronic message account is subject to unauthorized access. An unauthorized electronic message account can have any number of underlying causes and techniques including social engineering tactics, password leaks, account hijacking, impersonating, and the like. The reasons that a hacker would want to have access to an electronic message account can vary, but includes the ability to access personal information, health information, financial information, and the associated accounts. It is common for a user to use an email address as the primary identifier when logging into other systems. With access to an email account, a hacker can reset the user's password for a given website and the reset link can be sent to the email inbox so that the hackers can then reset the password allowing the hacker access to the website or account. Further, email is a common storage place for sensitive information including financial statements, agreements, personal photos, and other sensitive and private information including account and identifying information.
There is also a specific email attack that is more common with business emails. It targets business decision makers and seeks to have unauthorized financial transactions initiated by a hacker impersonating the business decision makers. A form of this attack is also known as conversation hijacking where the hacker attempts to insert themselves into existing business conversations to take money or personal information without permission. Another risk is when the account is subject to a takeover and the hacker uses the account for further illegal activity, such as the source of spam, phishing, scamming, spear-phishing, domain impersonation, brand impersonation, and the like. In one study, it was concluded that about 29 percent of Microsoft Office 365 accounts have been compromised. Using these compromised accounts, hackers were able to send in excess of 1.5 million malicious and spam emails.
Techniques used to take over an account include using login credentials from data breach databases, published in criminal forums, use of stolen passwords from personal email accounts to gain access to business email, social engineering tactics, and the like.
While these risks are growing, it is understood that the electronic message systems provide the ability to have very fast delivery of information from a remote geographic location, can be sent and received 24 hours a day, 365 days a year, can be accessed with any computer system using a cloud-based system so that personal devices are not required, are inexpensive and can be used on a one-to-one or one-on-one basis to procure its distribution. Therefore, it is unlikely that electronic message systems, including email, will be retired any time soon. Further, it is commonly stated that it is not a matter of whether a breach will occur, but when. Having tools and processes in place that can identify and prevent the user of a breached account would be of great importance.
There have been attempts to automatically filter or identify undesirable electronic messages that can be received from hackers. For example, U.S. Pat. No. 9,501,746 which discloses a system related to detecting bad actors that impersonate other people's identity in order to increase the likelihood of recipients opening these bad actors' messages and attachments. This patent states that this undesirable activity is generally referred to as “phishing” and specifically “spear phishing” when the recipient is targeted by the fake sender who is referred to as a “phisher.” This patent also states that these phishers send these “fake emails” seeking to increase their likelihood of successfully gaining unauthorized access to confidential data, trade secrets, state secrets, military information, and other information. The motivation of these phishers is typically for financial gain through fraud, identity theft, and/or data theft. The phishers may also be those who wish to disrupt normal operations. Phishing attempts have been associated with private entities, being state-sponsored, as well as being from foreign governments themselves. While detecting an unauthorized access attempt has some benefit, it would be desirable to have a system that can reduce or eliminate the risks when a breach occurs.
Another attempt to detect and/or handle targeted attacks is shown in U.S. Pat. Nos. 9,686,308 and 10,181,957 which discloses a system for detecting and/or handling target attacks in an enterprise's email channel. This patent discloses receiving aspects of an incoming electronic message addressed to a first email account holder, selecting a recipient interaction profile, and/or a sender profile from a plurality of predetermined profiles stored in a memory, determining a message trust rating associated with the incoming email message based upon the incoming email message, the selected recipient interaction profile, and/or the sender profile; and generating an alert identifying the incoming email message as including a security risk based upon the determined message's trust rating. However, these techniques are limited to preventing an attack, not reacting to one.
Typically, attempts to reduce email risks are directed to detecting and preventing attacks, not reacting to a successful attack. For example, U.S. Pat. No. 7,634,810 discloses a phishing detection module that detects a phishing attack in the communication by determining if the domain of the message source is similar to a known phishing domain, or by detecting suspicious network properties of the domain. This attempt requires that information about the message domain is known allowing bad actors to simply change domains to overcome this system.
Another attempt to detect, prevent, and provide notification of phishing attempts is shown in U.S. Pat. No. 10,404,745 which discloses the use of natural language techniques and information present in an email (namely the header, links, and text in the body) to detect phishing. This system is limited to an analysis of the email itself and occurs once the phishing attempt or attack has been initiated. While detection and prevention can be advantageous, a system that handles the success attack is needed. Unfortunately, the historical activities such as subscribing to a spam filter are no longer sufficient and a more sophisticated approach is needed. One strategy is to develop a layered approach which should include preventive measures at the perimeter and not just once the email arrives in the inbox or email system.
When an electronic message account is breached, there can be some indications that the breach has occurred. Some signs that can be used to determine that a breach has occurred include changing passwords, emails in an inbox that are not recognized, unexpected emails are received, IP addresses are present in a log, individuals in a contact list begin to receive spam messages from the account holder and message volumes and patterns change. However, these indicators require the user to note that change and potentially react.
While the behavior of the user has been the subject of some systems, such as in U.S. Pat. No. 11,019,000, these systems do not consider the identification or reaction to unauthorized access. This reference is limited to aid the account holder for managing inbound email by detecting, and configurably responding to, dynamically variable patterns of activity and behavior of the recipient. Unfortunately, this attempt to solve email management issues falls short when applied to unauthorized access and attacks. Further, the recipient must open, review, and take some action on the email for the system of this reference to properly operate.
U.S. Pat. No. 9,344,394 is also an attempt to improve management of email volume. This reference contends that it performs thread-based message prioritization by using metadata that can be extracted from a received electronic message. Again, this system operates on an email message that has already been received by the electronic message system. It seeks to prioritize emails based upon the thread information. U.S. Pat. No. 7,865,458 states that it is a method and system for enforcing rule selection on user email inboxes that includes an inbox monitor and administrative rules at an email server. Again, these systems require that the email arrives at the recipient's inbox while activity of the user with the user's inbox is not directed to the analysis and reaction to a breach.
There has been some attempt to detect breaches such as shown in United States Patent Application Publication 20190260780 which states that it is a cyber threat defense system protecting email networks with machine learning models. This system, however, is limited to the information that is contained in the email system without the ability to determine whether such data is consistent with disparate or remote information or system.
Therefore, it is an object of the system to provide for a computerized system that can determine a breach and react to the breach.
It is another object of the system to allow for the unauthorized account to
be deactivated or otherwise modified in response to a breach.
It is another object of the system to detect an unauthorized account by comparison to disparate and remote data associated with the account.
The construction designed to carry out the invention will hereinafter be described, together with other features thereof. The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein:
With reference to the drawings, the invention will now be described in more detail.
Referring to
Analysis server 116 can be adapted to receive information about messages originating from the sender's message system through several communications paths. For example, the analysis server can be within the recipient's domain 118 so that the sender message system and the analysis system 116 can be in communications and in the same domain. In the embodiment, the analysis system can receive the message, analyze the message, and send the message on to a transmission server 108. In one embodiment, the analysis system 116′ can receive the message, analyze the message, and send the message on to a transmission server 108 so that the analysis server is outside the recipient's domain.
The analysis server can be in communications with one or more disparate information sources 120 including the sender's schedule, office hours and patterns, time zone, geographic locations, vacation schedule, historical behavior including sending and receiving frequency and velocity and the like. The disparate information source can include information from the sender's message system itself such as login patterns, actions within the sender's account (e.g., message read, delete, reply, marking, forwarding, quarantine, and the like).
In one embodiment, prior to the message arising at the recipient message system 114, the message can be intercepted by the analysis server 116. The analysis server can be determined using the MX record information in one embodiment so that the electronic message routes through the analysis server instead of directly to a recipient message system. This allows the electronic message to be analyzed and potential warning or actions taken prior to the message being sent to the recipient's message system and even prior to the message being sent outside the sender's domain.
The analysis server can determine or receive from the sender's message system information such as temporal patterns, volume, frequency, velocity, and acceleration or declaration of sent messages. In one embodiment, the message activity can be tracked according to several temporal characteristics. For example, the number of emails that are sent in a day, week, or month. The sending of an email can be tracked according to the day of the week, such as a normal work week (e.g., Monday through Friday), or some other work schedule. The system can display the email activity in a graph such as the one shown in
where σ is the data standard deviation, N is the size of the sample set to be analyzed, xi is each value in the sample set and μ is the sample set mean. In one embodiment, the analysis server can determine the standard deviation which can indicate the number of emails sent in a day is close to the average and therefore very consistent. If a single day has a number of emails that is higher than the average and the standard deviation is low, then it can indicate that there is abnormal email activity associated with that user (i.e., sender) account. Such activity could mean that the email account has been subject to unauthorized access and being used for spam or other undesirable purposes. In one embodiment, the analysis server creates a warning of potential unauthorized access to the sender's account when the current message behavior deviates from the baseline pattern by one standard deviation. Recognizing, however, that user's occasionally deviate from the baseline pattern, the analysis server is adapted to receive an approval of the current message behavior representing that the current message behavior is acceptable and that it should not cause the system to generate a warning based upon the current message behavior. Upon receiving such an approval, the analysis server can update the baseline behavior pattern and/or the behavior dataset to account for the current message behavior that has been approved so that similar behavior is less likely to trigger a warning in the future.
The analysis server can also determine a standard deviation for a group of users or entire message system and, when the number of emails being sent increases abruptly, it can indicate that the one or more email accounts or even the sender's message system has been subject to an unauthorized access and is being used for spam or another undesirable purpose.
The analysis server can also normalize the message historical information for analysis and can have the following functionality in its computer readable instructions allowing the analysis to serve and perform for a specific and specialized purpose:
Referring to
Referring to
In one embodiment, the analysis server can determine if there is a potential unauthorized access situation by using tools such as a Z-score. The analysis server can use the Z-score to determine if messages being sent are within an acceptable range or if there is an anomaly. Generally, the Z-score provides an indication that email sending volumes, values, or other measures distance from the mean. The Z-score can be calculated by the following:
Where x is the value to be measured, μ is the mean of the historical or set to be examined and σ is the standard deviation. In one embodiment, a Z-score greater than 1.0 can indicate that unauthorized access has occurred.
In one embodiment, the Z-score can be modified, especially for users with email sending patterns that are not normally distributed or when the user is a new user and there is not a large historical dataset. In these situations, the following modified Z-score can be used so that the analysis server is not overly sensitive to extreme values of emails being sent from the user's account.
The modified Z-score can assist with reducing the number of false positive hits for potential unauthorized access determinations. Other techniques that can be used by the analysis server and included in its computer readable instructions include the use of a interquartile range, box plot, and histogram. When analyzing new users or users with sporadic email sending patterns, the histogram can include logarithmic or square root values to seek a more normalized dataset set analytical result.
In one embodiment, the historical email sending data (e.g., volume, time, velocity, and the like) can be reviewed when the data is collected for a user or enterprise wide and on a daily or hourly frequency. According to the dataset, the analysis server can select an analysis model by using various models and determining the model that has the least errors. Errors can be determined by using the following equation embodied in computer readable instructions:
where MAPE is the mean absolute percentage error, n number of fitted points, Ai is the actual value and Fi is the furcate value. The analysis server can overly the email sending data with seasonal correction data for a more accurate determination of the user's email sending patterns. For example, the analysis can adjust the dataset used for comparison with current activity for holiday including Memorial Day, Independent Day, Thanksgiving, Black Friday, Cyber Monday, December 24-26, January 1 and December 31, where reduced email sending use may be seen. Further, the analysis server can also correct for the potential increased use of email in the days prior to such holidays.
Referring to
The analysis server can also develop a dynamic email sending pattern that can be associated with the user according to historical emails sent that is unique for each user. The pattern can be an analysis, including statistical analysis, of the emails sending pattern over some period of time. The sending pattern can be the behavior dataset indicative of a baseline pattern of sent messages which is used for comparison to a current message behavior associated with the sender's email account for purposes of determining whether there are anomalies which can indicate that there is unauthorized access to the sender's email account. The analysis server can also create or access a status data set associated with the sender, which may include information about the sender, including the sender's: schedule information, temporal information, location, login activity, logoff activity, mailbox activity, and any combination thereof. With respect to the sender's mailbox activity, the analysis server can also generate, analyze and/or receiving information regarding the sender's behavior with respect to email messages in the sender's account, including reading the message, deleting the message, preparing reply to the message, forwarding the message, quarantining the message or any combination thereof. The baseline pattern of sent messages associated with the user is calculated based, at least in part, upon the behavior dataset and the status dataset associated with the user. For example, the analysis server can determine that the user is or typically goes on holiday the first week of August and therefore reduce the potential for incorrectly determining reduced use of emails is during a holiday. The system can also determine that increased email use during a holiday can indicate unauthorized access. The system can also determine that the sender is not logged into his or her email account so that when an email is sent from the sender's account, the system will create a warning that unauthorized access to the sender's account is likely to have occurred. This warning may be transmitted to an administrator associated with the sender's message system. Whatever the triggering event may be that causes the system to generate a warning, the system may additionally or alternatively quarantine the message associated with the current message behavior that deviates from the baseline pattern and/or the behavior criteria associated with the sender.
These determinations can be made within a department, section, or enterprise wide. For example, the analysis server can determine that the business associated with the electronic message system is closed for the holiday between December 20 and January 2. Therefore, any increased email sending activity during this time can indicate unauthorized access.
In one embodiment, the analysis server can receive scheduling information that can represent the work hours of the user associated with an email account. In the event that there is email activity originating from the user's email account that is outside working hours as determined by the work schedule, the analysis server can indicate that the account may have been subject to an unauthorized access and being used for spam or other undesirable purpose.
In one embodiment, the analysis server can receive environmental information such as weather and can overlay this information with the email sending traffic. For example, if the electronic system is associated with a construction company and there is weather prohibiting a project from moving forward, email traffic for construction workers in the field may increase (e.g., not on the job site).
The analysis system can also be in communications with an access control system associated with the user. Generally, the access control system can control who is allowed at a location and when they are allowed at that location. If the access control system shows that the user is not at a location known to have the user's computer device, the analysis server can determine that there is email activity from the user's account when the user is not present to access the account.
The analysis server can also be in communications or receive information about the sender's location from a device such as a portable phone or smartphone. If the portable device information shows that the user is not at a location known to have the user's computer device, the analysis server can determine that there is email activity from the user's account when the user is not present to access the account. In one embodiment, the user account can include a sensitivity value that can represent the tolerance of deviations that trigger a warning or action for that account. For example, if the user is an executive in a large organization, the tolerance for deviation from standard email patterns can be reduced. For example, the CEO suddenly begins to send two or three times the number of emails to employees, especially to others with lower tolerances, it can indicate an unauthorized access.
In one embodiment, the email send statistics can be combined with email content that can be determined from past information. Referring to
Referring to
The analysis server can also analyze the attachment size for an indication that the message potentially contains harmful content. When the size of the attachment changes from historic values, it can indicate unauthorized access. This can be true for both an increase and decrease in attachment seize as malware can be under 100 kB and exceeds 300 kB. Further, malware can exist in multiple file types such as .XLS, .PDF, .JS, .VBS, .DOCX, .DOC, .WSF, .XLSX, .EXE, and .HTML so that an increase in any of these file types in messages can indicate unauthorized access.
Referring to
Referring to
Generate a warning that can be transmitted to the electronic message system, administrator, recipient, third party (e.g., blacklist), reputation administrator, or other third party.
Lock the account of the sender.
Quarantine outbound electronic messages.
Delete the outbound messages.
Modify the header of the message indicating that the email is or may be from a compromised account.
Require a password reset for the sender's account.
Require multifactor authentication for the sender's account.
Initial a scan of the electronic message system of the user's account.
Require a chance in security questions.
And any combination of the above.
In one embodiment, the analysis server can edit the header information with triggers or other information that can indicate that the message may have come from a comprised account. In this example, the recipient's message system can determine the appropriate action. The triggers that are placed on the header information could result from any number of determinations by the analysis server and can represent level of anomalies from none, suspicious, probably unauthorized access, unauthorized access and the like. In this case, the analysis server does not actually have to take action according to the trigger and the trigger is simply associated with the electronic message. The trigger can be associated with the electronic message by editing the header information, adding information to the electronic message subject, adding information to the electronic message contact, adding an attachment and any combination thereof. Therefore, in one embodiment, the analysis server is amending the electronic message, including amending its header information, so that subsequent action could be taken, but does not necessarily have to be taken. This structure provides increased functionality and even security for existing electronic message systems that would not otherwise be possible.
The analysis server can also perform a security check on the sender electronic message system that could include a TLS encryption analysis, a MX record exposure, a DKIM presence, a SPF presence, a DMARC presence, a reputational information, a reverse DNS lookup consistency, a tracking item, information concerning other users (e.g., did other users delete, move, not open, open or take other cation on the same or similar electronic message) and any combination thereof
The analysis can also generate a security score according to the analysis described herein. The analysis can determine tracking information such as if the message sent from the potentially compromised account includes a tracking item or that a tracking item has been or should be added. In one embodiment, the tracking information is a tracking pixel or image that can be added to the message email that is sent. The analysis can determine that the tracking items is present and can take action or provide a trigger in the message for subsequent action (e.g., warning that a tracking pixel is present).
The message can be a computer-generated message or can be a sender generated message. The message can be a message composed by a human sender and provided to the sender's message system in digital form using computer readable code or human readable code such as human readable text.
The system described herein is directed to a series of acts that can detect unauthorized access. The computerized system is one that is at least directed to a process. The system can identify and potentially act upon electronic messages in an electronic message system according to the comparison with historical activity of the user account. The processes and procedures that are described herein can be actuated by a computer processor that executes computer readable instructions to provide the functionality herein.
It is understood that the above descriptions and illustrations are intended to be illustrative and not restrictive. It is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. Other embodiments as well as many applications besides the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the invention should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The omission in the following claims of any aspect of subject matter that is disclosed herein is not a disclaimer of such subject matter, nor should it be regarded that the inventor did not consider such subject matter to be part of the disclosed inventive subject matter.
This application claims priority from U.S. Provisional Patent Application 63/398,142 filed Aug. 15, 2022, U.S. Provisional Patent Application 63/398,137 filed Aug. 15, 2022, U.S. Provisional Patent Application 63/398,132 filed Aug. 15, 2022, and U.S. Provisional Patent Application 63/398,127 filed Aug. 15, 2022 each incorporated herein by reference.
Number | Date | Country | |
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63398127 | Aug 2022 | US |