DETECTION OF REMOTE FRAUDULENT ACTIVITY IN A CLIENT-SERVER-SYSTEM
20200213333 ยท 2020-07-02
Inventors
- Ingo Deutschmann (Frankleben, DE)
- Per Burstrom (Lulea, SE)
- Philip Lindblad (Lulea, SE)
- David Julitz (Weissenfels, DE)
Cpc classification
H04L63/0428
ELECTRICITY
H04L63/145
ELECTRICITY
H04L63/0861
ELECTRICITY
H04L63/1466
ELECTRICITY
International classification
Abstract
Detecting unauthorized access to a device is detected in embodiments of the disclosed technology. After downloading a webpage, code is executed in a browser to scan network ports and determine which ports are open. Further webpage content sent from a web server is determined and/or modified in embodiments of the disclosed technology based on which ports are open. In some embodiments, when a particular port or ports are already in use it is determined that a malfeasant actor has access to the end user device and as such, sensitive data or secure data which is intended for a specific user is no longer sent to the end user device.
Claims
1. (canceled)
2. A method of port scanning to prevent data theft, comprising the steps of: receiving on a server, via a wireless or wired communication channel, a request for secure data delivered via a first software port; sending at least some of the secure data via said wireless or wired communication channel, said secure data including instructions to execute code upon reception by an end user device, execution of said code causing the end user device to attempt to open a network connection via at least a second software port and to collect behavioral characteristics of a user on the end user device, the behavioral characteristics including statistical measures of at least one of a plurality of key press times, key flight times, mouse movement, and pressure sensor readings; matching the collected behavioral characteristics with a prior usage of the user's known behavioral characteristics to determine the presence of a remote access trojan (RAT) signature or malfeasant automated program (BOT) signature; receiving data to determine whether said at least said second software port is in use; and delivering modified data to detect a malfeasant actor, via said wireless or wired communication channel, if it is determined that said at least said second software port is in use or if the presence of a RAT signature or BOT signature is determined.
3. The method of claim 2, wherein said at least said second software port is a plurality of second software ports and said code, when executed, attempts to open a network connection on each of said plurality of second software ports.
4. The method of claim 3, comprising additional steps of: authenticating identity of a user carrying out said request for said secure data; receiving additional requests from said user for further secure data; sending at least some additional secure data via said wireless or wired communication channel to said user wherein each additional request comprises additional instructions to execute code which upon execution by a device used by said user attempts to open a network connection on a plurality of additional software ports.
5. (canceled)
6. (canceled)
7. The method of claim 3, wherein said code is adapted to scan additional software ports and report availability of said additional software ports after a request for additional secure data is made.
8. (canceled)
9. A method of delivering webpages comprising the steps of: delivering a webpage with a request for user authentication; authenticating said user and embedding code in a second webpage causing a browser to determine behavioral characteristics of said user and as a result of certain behavioral characteristics, scan a plurality of software ports, wherein said behavioral characteristics are statistical measures of at least one of a plurality of key press times, key flight times, mouse movement, and pressure sensor readings; matching the collected behavioral characteristics with a prior usage of said user's known behavioral characteristics to determine the presence of a remote access trojan (RAT) signature or malfeasant automated program (BOT) signature; receiving data based on which it is determined that a software port of said plurality of software ports is in use; modifying content sent in further webpages based on a determination that said software port is in use or if the presence of a RAT signature or BOT signature is determined.
10. The method of claim 9, wherein a version of said code is executed upon or after download of content from each of a plurality of unique uniform resource locators (URLs).
11. The method of claim 10, wherein each time said code is executed after download of content from a unique URL, additional ports of said plurality of software ports are scanned.
12. The method of claim 11, wherein said scan takes place only after the entirety of said content is rendered.
13. The method of claim 11, wherein said modifying is based on a determination that said software port in said use is a port used by a malfeasant.
14. The method of claim 11, wherein a quantity and/or rate of said plurality of software ports being scanned is based on available network bandwidth of a network node and/or processor usage where said software ports are being scanned.
15. A method, comprising the steps of: delivering a combination of: a) data based on which a remote device renders content designed for human viewing thereof; and b) instructions to execute code designed for execution by a remote device on a network, wherein said code scans network ports of said remote device where said content has been rendered and collects behavioral characteristics of a user on the remote device, the behavioral characteristics including statistical measures of at least one of a plurality of key press times, key flight times, mouse movement, and pressure sensor readings; receiving from said remote device an indication that a specific port of said network ports is already in use or an indication that the behavioral characteristics include a remote access trojan (RAT) signature or a malfeasant automated program (BOT) signature; and denying access to authenticated data if an indication that a specific port of said network ports is already in use is received or if an indication that the behavioral characteristics include a remote access trojan (RAT) signature or a malfeasant automated program (BOT) signature is received; wherein said step of delivering to said device is carried out a first time and a second time, wherein, in response to a first execution of said code following said delivering of instructions to said device said first time, a first subset of said network ports are scanned, and in response to a second execution of said code following said delivering of instructions to said device said second time, a second subset of said network ports are scanned, said second subset of said network ports being different from said first subset of said network ports.
16. (canceled)
17. The method of claim 15, wherein said code determines that said content has been rendered before said code scans network ports.
18. The method of claim 15, wherein said code designed for execution by said remote device on said network scans network ports at a rate based on one of available network bandwidth of said remote device and processor usage.
19. (canceled)
20. (canceled)
21. The method of claim 1, wherein said code is adapted to scan at least one other software port, different from said second software port, and to report availability of said at least one other software port, after a pre-defined period of time has passed from said receiving said request for secure data without receiving another request for secure data.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0021]
[0022]
[0023]
[0024]
DETAILED DESCRIPTION OF EMBODIMENTS OF THE DISCLOSED TECHNOLOGY
[0025] After downloading a webpage, code is executed in a browser to determine behavioral characteristics of a user of the browser and to scan network ports and determine which ports are open. Further webpage content sent from a web server is determined and/or modified in embodiments of the disclosed technology based on the behavioral characteristics and/or which ports are open. In some embodiments, when the behavioral characteristics discloses the use of a RAT or BOT software, the set of ports to scan is determined from prior knowledge of the specific type of RAT or BOT. In some embodiments, when a particular port or ports are already in use it is determined that a malfeasant actor has access to the end user device and as such, sensitive data or secure data which is intended for a specific user is no longer sent to the end user device. In some embodiments, the RAT or BOT behavioral characteristics are logged and stored by the behavioral module (to allow faster identification of such in future uses in some embodiments).
[0026] Embodiments of the disclosed technology will become more clear in view of the following description of the figures.
[0027]
[0028]
[0029] At this point, the end user device 120 carries out steps in embodiments of the disclosed technology, namely, rendering the viewable content in step 240 and executing code in step 250. The code causes the end user device 120 to collect behavioral characteristics of the user of end user device 120, and in step 260, scan software ports and determine which ports are open. The behavioral characteristics are sent to the server 110, which performs an analysis of the behavioral characteristics and based on this updates the code to be executed in step 230 again. The determination 270 of which ports are open can be based on being denied access to a port and while this step is shown as being carried out by the end user device 120, the actual determination or action which is based on the information gleaned by scanning the software ports can be carried out by the server. Referring still to
[0030] During the course of an authenticated session (a series of data exchanges between the server and end user device where a first authentication scheme, such as received username and password, is used to access secure data for a particular user determined to be operating the end user device) a plurality of webpages and other data may be sent in step 290. This continues or can continue with back and forth data requests and responses thereto in step 290 and then again in step 230. Content is only modified or restricted in step 299, in embodiments of the technology, when it is determined that a RAT or BOT is communicating or may be communicating with the end user device 120 due to either a RAT/BOT behavior signature being detected or a specific port being unavailable which is associated or used by a known RAT or BOT.
[0031] Referring again to
[0032]
[0033] In step 320, the CPU (central processing unit) usage is determined for the end user device 120. In order to avoid degradation to the user experience and/or system performance of the end user computing device, in step 320 it is determined that if CPU usage is above a threshold that port scanning speed or quantity is throttled or reduced in step 335 due to a determination, in step 330, of limited CPU usage available. Likewise, if the available bandwidth in step 325 is determined to be limited in step 330, then the speed or quantity of ports scanned is throttled. In this case, bandwidth can refer to the maximum transfer speed between the server 110 and end user device 120, ping time, latency, or information known about the network on which the IP address of the end user device is situated. A cellular or satellite data connection, for example, may be given less ports to scan or ports per minute to scan than a wired fiber optic data connection to the end user.
[0034] In step 340 it is determined if ports have been previously scanned for the particular end user computing device 120 or scanned during a particular authenticated session. It might be decided, and programmed into the code which has instructions carried out by the end user device 120, to scan all 65535 ports in sequence, randomly, or based on most likely ports used by a RAT or BOT especially in view of a present known threat, as determined by the behavioral analysis, and common RAT or BOT used at the time. RATs commonly use port 80, 443, 8000, or 8080 which while typically also used for a web server, are ports that an end user computing device typically does not use. A Windows, Macintosh, or Linux machine used by an end user to access his/her bank, for example, probably is not running a web server. Therefore, if these ports are found to be unavailable than it may be indicative of a RAT or BOT running and action might be taken to restrict sending of sensitive data to such a machine. In step 50, prior ports scanned might be excluded from a future scan and/or new ports are selected to be scanned.
[0035] In any of the above cases, after it is determined which ports to scan and a speed at which to scan the ports, then the ports are scanned in a version of carrying out the coded instructions for same in step 390. The data about which ports are open for use or unavailable is then sent to the server in step 280 for processing and possibly restricting access to sensitive data, as described with reference to
[0036] Describing the process of port scanning at a lower level, this can be carried out by a web browser by way of JavaScript in embodiments of the disclosed technology. This uses existing software. Some ways to implement port scanning mechanisms inside a browser are by injecting image elements into the DOM (document object model), by leveraging the XMLHttpRequest object or by leveraging WebSockets. The injection of new DOM elements works, because some DOM elements are triggering the browser to open connections and trying to download additional information. This will work for example for HTML <img> elements. The src attribute with some local address including some particular port of interest can be used for testing (i.e. https://127.0.0.1:8080). By JavaScript it is possible to hook into some event handling mechanisms for these particular elements. Listening to the events will reveal if the port is open or not. An example of code to carry out same follows.
TABLE-US-00001 function PortScannerImg( ) { this.timeout = 1000; this.run = function (ip, scan_list) { var self = this; scan_list.forEach(function (item, index) { var img = new Image( ); var handler = function (e) { if (!img) return; img = undefined; item.state = open; }; img.src = http:// + ip + : + item.port + / + Math.floor(Math.random( ) * 1000000) + .png; img.onerror = handler; img.onload = handler; setTimeout(function ( ) { if (!img) return; img = undefined; item.state = closed; }, self.timeout); }); } } var scan_list = [ {port: 21}, {port: 22}, {port: 25}, {port: 110} {port: 8080}, {port: 8081}, {port: 8443}, {port: 3306}, {port: 3389} ]; var scanneIlmg = new PortScannerImg( ); scannerImg.run(127.0.0.1, scan_list);
[0037] Leveraging XMLHttpRequest is another way to carry out port scanning. In this case an AJAX Request is issued to the localhost IP address with some specific port of interest. Here again the different events can be handled with the aid of JavaScript to make the decision if a port is open or not.
TABLE-US-00002 function PortScannerXMLHttp( ) { this.run = function (ip, scan_list) { scan_list.forEach(function (item, index) { var xhttp= new XMLHttpRequest( ); xhttp.onreadystatechange = function( ) { if (xhttp.readyState = = 4) { if (!item.state) item.state = open; } }; xhttp.open(GET, http:// + ip + : + item.port, true); xhttp.send( ); setTimeout(function ( ) { if (!item.state) item.state = closed; }, 1000); }); } } var scan_list2 = [ {port: 21},{port: 22},{port: 25},{port: 110}, {port: 8080},{port: 8081},{port: 8443}, {port: 3306},{port: 3389} ]; var scannerXMLHttp = new PortScannerXMLHttp( ); scannerXMLHttp.run(127.0.0.1, scan_list2);
[0038] A third method to detect open ports is by way of WebSockets. In this case it is possible to track how much time is needed to change the readyState property. Depending on how long it takes to change the state one can conclude if a port is open or closed.
[0039]
[0040] While the disclosed technology has been taught with specific reference to the above embodiments, a person having ordinary skill in the art will recognize that changes can be made in form and detail without departing from the spirit and the scope of the disclosed technology. The described embodiments are to be considered in all respects only as illustrative and not restrictive. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. Combinations of any of the methods, systems, and devices described herein-above are also contemplated and within the scope of the disclosed technology.