Authored by malvuln | Site malvuln.com

Backdoor.Win32.Guptachar.20 malware suffers from an insecure credential storage vulnerability.

Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2022
Original source: https://malvuln.com/advisory/857999d2306f257b80d1b8f6a51ae8b0.txt
Contact: [email protected]
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Guptachar.20
Vulnerability: Insecure Credential Storage
Description: The malware runs a web server on TCP port 2015 (default) and uses BASIC authentication. The credentials "hacker01:imchampgr8" get stored in a .NFO information file named "GPTCR.NFO" under Windows dir base64 encoded and hidden among many junk NULL bytes.
Family: Guptachar
Type: PE32
MD5: 857999d2306f257b80d1b8f6a51ae8b0
Vuln ID: MVID-2022-0631
Dropped files: GPTCR2.exe
Disclosure: 08/08/2022

Exploit/PoC:
import base64
base64.b64decode("aGFja2VyMDE6aW1jaGFtcGdyOA==")
b'hacker01:imchampgr8'

Web URLs available on the infected host.

http://192.168.18.125:2015/execute.html
http://192.168.18.125:2015/browse.html
http://192.168.18.125:2015/upload.html
http://192.168.18.125:2015/screenshot.html
http://192.168.18.125:2015/keylog.html
http://192.168.18.125:2015/display.html
http://192.168.18.125:2015/shutdown.html
http://192.168.18.125:2015/servopts.html


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).