Chess tactics for beginners
- Chess tactics for beginners .exe#
- Chess tactics for beginners code#
- Chess tactics for beginners download#
- Chess tactics for beginners windows#
Fortinet has been identified it as virus “W32/Delf.EFUQ!tr”. The properties of the downloaded fileĪfter a quick analysis we can see that this is a new variant of Strictor, which is ransomware. The file “disk.exe” is executed by calling “oShell.Run”. When it is executed it downloads a file from “hxxp://****/dix/disk” into “%appdata%\disk.exe”.
Chess tactics for beginners code#
When going through all the code you can easily understand its purpose. The VBA code extracting vbs code from TextBox control into “gtls.vbs”.The VBA code is designed to extract the malicious code from stream “_VBA_PROJECT_CUR/UserForm1/o” into a file called “gtls.vbs” and then execute it. Once this sample is opened in Excel, the function “Workbook_Open” inside the stream “ThisWorkbook” will be called if the Macro security option is enabled. Its “Text” property contains malicious code, which is invisible by default. Inside the VBA project there is a “TextBox” control. The OLE structure of this sampleįrom the parsing result of the OLE file analysis tool, we can see the VBA code is stored in streams “_VBA_PROJECT_CUR/VBA/ThisWorkbook”, “_VBA_PROJECT_CUR/VBA/Module1”, and “_VBA_PROJECT_CUR/UserForm1/o”. This sample contains modules and controls. Excel Malware Sample 2Īnother Excel malware sample was first collected in our system on Feb 27, 2017. They are used to spread different kinds of malware, including Trojans, Ransomware, Spyware, Bots, etc. In our collection system we gathered lots of Excel samples containing similar VBA code. Finally, the stolen credential data is encrypted and sent to its C&C server.įor more information about Dyzap, you can read the blog from Bahare Sabouri and He Xu.
Chess tactics for beginners .exe#
exe file called “paray.txt”, the new variant of Dyzap, and run it to keep stealing credentials from infected systems. exe file is a downloader of Dyzap malware. exe file into “%appdata%.exe” and execute it.
Chess tactics for beginners download#
As a result, executing this command will download an. “cmd.exe /c” initiates running a new cmd shell, executing the command specified by the string, and terminating it.
Chess tactics for beginners windows#
So, after removing all the ‘^’ symbols and changing all the characters to lowercase because Windows commands are not case-sensitive, the string looks clearer and is easier to understand: There are many ‘^’ symbols in this command, but we can directly ignore them because ‘^’ in DOS shell is the escape character. We can see a DOS command will be executed by calling cmd.exe.
![chess tactics for beginners chess tactics for beginners](https://m.media-amazon.com/images/I/411oOGNfOxL.jpg)
It looks weird because of the code obfuscation. Debugging the VBA code with Microsoft Visual Basic for ApplicationsĪs analyzed in Figure 3, here is the string in the variable “ugsubpox”:.In this sample, the first parameter “ugsubpox” holds the command string. The final string is the malicious command being executed by the “Shell” function. Finally, it puts the strings together in a special order to generate the final command string.Īctually, this is a kind of code obfuscation technique used to avoid being detected and analyzed. Second, it generates some strings by concatenating elements of the arrays by their indexes. First, it creates some arrays with short names by calling the Array function. In this sample, the “Shell” function is called at the bottom to execute the malicious command. Based on our analysis of other malicious VBA-based samples, the functions “ShellExecute”, “Shell”, “WScript.Shell”, and “Run” are usually called to execute DOS commands. So I extracted the VBA code from it.Īs you can see from the above VBA code, there is a function named “Auto_Open”, which is called automatically when the file is opened in Excel. The OLE structure of this sampleįrom the parsing result of the OLE file analysis tool, the malicious VBA code exists in the Module1 stream. Here is the OLE structure of this sampleįigure 2.Its original file name is “payment.xls”, which was detected as virus “WM/Agent.D9E2!tr.dldr” by Fortinet because it contains malicious VBA code. The file in this example is an OLE format Excel file that was collected on Feb 27, 2017. Once the macro function is enabled, the malicious VBA code inside the sample is executed.
![chess tactics for beginners chess tactics for beginners](https://chessfox.com/wp-content/uploads/2018/08/chess-tactics-for-beginners-pin.png)
When the infected file is opened in Excel, a message pops up asking the user to enable the macro security option by clicking the “Enable Content” button. I’ll use two examples to explain how Excel files can be used to spread malware. Normally, VBA is used to develop programs for Excel to perform some tasks. VBA is a programming language used by Microsoft Office suite. xlsm) that spread malware by executing malicious VBA (Visual Basic for Applications) code. Lately, Fortinet has collected a number of email samples with Excel files attached (.xls. Now it seems that it is becoming more and more popular to spread malware using malicious Excel files. Over the last few years we have received a number of emails with attached Word files that spread malware.