Review reviewCritical

CVE-2010-20103

ProFTPD Project ProFTPD (Professional FTP Daemon), proftpd

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: 9.3
EPSS: 5.09%
CISA KEV: Not listed
Published: 2025.08.21

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability5.09%

Technical severityCVSS 9.3

Vulnerability overview

Affected product and versions

Product: ProFTPD Project ProFTPD (Professional FTP Daemon), proftpd
Affected versions: >= 1.3.3c, 1.3.3
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that ProFTPD Project ProFTPD (Professional FTP Daemon), proftpd and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS: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
CWE: CWE-912