ProftpdApplication · Proftpd Project

CVE-1999-0911

HIGH · 10.0 CVSS v2.0 Published 1999-08-27
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Buffer overflow in ProFTPD, wu-ftpd, and beroftpd allows remote attackers to gain root access via a series of MKD and CWD commands that create nested directories.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Buffer overflow vulnerability in ProFTPD, wu-ftpd, and beroftpd allows remote attackers to gain root privileges via specially crafted MKD (make directory) and CWD (change working directory) commands that create deeply nested directory structures, causing a buffer overflow when the server processes the pathname.

MitigationUpgrade affected FTP servers to patched versions or migrate to modern, supported FTP server implementations. If legacy systems must maintain these FTP services, implement network segmentation and restrict FTP access to trusted sources only.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
ProftpdApplication
Affected:= 1.2_pre1= 1.2_pre2= 1.2_pre3= 1.2_pre4= 1.2_pre5

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete

AV:N/AC:L/Au:N/C:C/I:C/A:C

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify ProFTPD version
    Run 'proftpd -v' or check the FTP server banner using 'ftp localhost' or 'nc -v <server> 21'
    Affected if The version displayed is 1.2_pre1, 1.2_pre2, 1.2_pre3, 1.2_pre4, or 1.2_pre5
  2. Verify FTP service is running
    Check for running FTP processes using 'ps aux | grep ftp' or check if port 21 is listening with 'netstat -an | grep :21' or 'ss -tlnp | grep :21'
    Affected if Port 21 is open and an FTP server process is active
  3. Confirm network accessibility of FTP
    Check if port 21 is exposed to network using 'nmap -p 21 <your_ip>' or review firewall rules with 'iptables -L' or 'firewall-cmd --list-all'
    Affected if The FTP port is accessible from network hosts beyond localhost
  4. Check for anonymous FTP access
    Review FTP configuration file (commonly /etc/proftpd.conf or /etc/ftpaccess) for 'Anonymous' user directives
    Affected if Anonymous FTP access is enabled in the configuration

Your environment is affected if ProFTPD version 1.2_pre1 through 1.2_pre5 is running and the FTP service is network-accessible.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade affected FTP servers to patched versions or migrate to modern, supported FTP server implementations. If legacy systems must maintain these FTP services, implement network segmentation and restrict FTP access to trusted sources only.

Fix this in Proftpd Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-1999-0911 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-1999-0911 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data