CVE-2010-20103
published 2025-08-20CVE-2010-20103: A malicious backdoor was embedded in the official ProFTPD 1.3.3c source tarball distributed between November 28 and December 2, 2010. The backdoor implements a…
PriorityP188critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
4.75%
90.8th percentile
A malicious backdoor was embedded in the official ProFTPD 1.3.3c source tarball distributed between November 28 and December 2, 2010. The backdoor implements a hidden FTP command trigger that, when invoked, causes the server to execute arbitrary shell commands with root privileges. This allows remote, unauthenticated attackers to run any OS command on the FTP server host.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| proftpd | proftpd | — | — |
| proftpd_project | proftpd | — | — |
Detection & IOCsextracted from sources · hover to see the quote
commandHELP ACIDBITCHEZ
versionProFTPD 1.3.3c
- →Detect exploitation attempts by monitoring FTP traffic for the hidden backdoor trigger command 'HELP ACIDBITCHEZ' sent to port 21.
- →Flag any FTP server banner advertising 'ProFTPD 1.3.3c' as potentially running the backdoored binary; the compromised tarball was distributed between November 28 and December 2, 2010. ↗
- →A server response that does NOT contain '502 Unknown command' after sending 'HELP ACIDBITCHEZ' is a strong indicator the backdoor is active and the command was accepted.
- ·The backdoor is only present in the official source tarballs (proftpd-1.3.3c.tar.bz2 and proftpd-1.3.3c.tar.gz) distributed during the specific window; binaries compiled from uncompromised sources or other versions are not affected. ↗
- ·Exploitation requires no authentication; any remote attacker can trigger the backdoor command and gain root-level shell execution without credentials. ↗
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv4.09.3CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vulncheck9.3CRITICAL
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GHSA
GHSA-xm7r-423x-5463: A malicious backdoor was embedded in the official ProFTPD 1
ghsa_unreviewed·2025-08-20
CVE-2010-20103 [CRITICAL] CWE-912 GHSA-xm7r-423x-5463: A malicious backdoor was embedded in the official ProFTPD 1
A malicious backdoor was embedded in the official ProFTPD 1.3.3c source tarball distributed between November 28 and December 2, 2010. The backdoor implements a hidden FTP command trigger that, when invoked, causes the server to execute arbitrary shell commands with root privileges. This allows remote, unauthenticated attackers to run any OS command on the FTP server host.
VulnCheck
proftpd proftpd Hidden Functionality
vulncheck·2010·CVSS 9.3
CVE-2010-20103 [CRITICAL] proftpd proftpd Hidden Functionality
proftpd proftpd Hidden Functionality
A malicious backdoor was embedded in the official ProFTPD 1.3.3c source tarball distributed between November 28 and December 2, 2010. The backdoor implements a hidden FTP command trigger that, when invoked, causes the server to execute arbitrary shell commands with root privileges. This allows remote, unauthenticated attackers to run any OS command on the FTP server host.
Affected: proftpd proftpd
Required Action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Exploitation References: https://www.cve.org/CVERecord?id=CVE-2010-20103; https://www.vulncheck.com/advisories/proftpd-backdoor-command-execution
No detection rules found.
Nuclei
ProFTPd-1.3.3c - Backdoor Command Execution
nuclei·CVSS 9.3
CVE-2010-20103 [CRITICAL] ProFTPd-1.3.3c - Backdoor Command Execution
ProFTPd-1.3.3c - Backdoor Command Execution
ProFTPD 1.3.3c contains a command injection backdoor caused by a hidden FTP command trigger in the source tarball, letting remote unauthenticated attackers execute arbitrary shell commands with root privileges.
Template:
id: CVE-2010-20103
info:
name: ProFTPd-1.3.3c - Backdoor Command Execution
author: pussycat0x
severity: critical
description: |
ProFTPD 1.3.3c contains a command injection backdoor caused by a hidden FTP command trigger in the source tarball, letting remote unauthenticated attackers execute arbitrary shell commands with root privileges.
impact: |
Unauthenticated attackers can execute arbitrary shell commands with root privileges by sending specially crafted HELP commands that trigger the hidden backdoor in the compromised sou
Metasploit
ProFTPD 1.3.3c Backdoor Command Execution
metasploit
ProFTPD 1.3.3c Backdoor Command Execution
ProFTPD 1.3.3c Backdoor Command Execution
This module exploits a malicious backdoor that was added to the ProFTPD download archive. This backdoor was present in the proftpd-1.3.3c.tar.[bz2|gz] archive between November 28th 2010 and 2nd December 2010.
http://www.proftpd.org/https://advisories.checkpoint.com/defense/advisories/public/2011/cpai-2010-151.html/https://github.com/proftpd/proftpdhttps://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/ftp/proftpd_133c_backdoor.rbhttps://web.archive.org/web/20111107212129/http://rsync.proftpd.org/https://www.exploit-db.com/exploits/15662https://www.exploit-db.com/exploits/16921https://www.vulncheck.com/advisories/proftpd-backdoor-command-executionhttps://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/ftp/proftpd_133c_backdoor.rbhttps://www.exploit-db.com/exploits/15662https://www.exploit-db.com/exploits/16921
2025-08-20
Published
Exploited in the wild