Critical severity · published Aug 20, 2025
CVE-2010-20103
A malicious backdoor was embedded in the official ProFTPD 1.3.3c source tarball distributed between November 28 and December 2, 2010
9.8
CVSS
13.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)13.8% · higher than 96% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PR
Proftpd · Proftpd
1.3.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2010-20103
CVE.org
https://www.cve.org/CVERecord?id=CVE-2010-20103
Product
http://www.proftpd.org/
Third Party Advisory
https://advisories.checkpoint.com/defense/advisories/public/2011/cpai-2010-151.html/
Product
https://github.com/proftpd/proftpd
Exploit
https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/ftp/proftpd_133c_backdoor.rb
Release Notes
https://web.archive.org/web/20111107212129/http://rsync.proftpd.org/
Exploit
https://www.exploit-db.com/exploits/15662
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