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Critical ProFTPD Vulnerability Allows Remote File Access

A serious security flaw has been found in ProFTPD, a common FTP server software. This flaw lets attackers remotely read and write files without permission. It is actively being exploited, so urgent action is needed to protect your systems.

09 October 2026

Reference: CVE-2015-3306

1. What is being reported?

The mod_copy feature in ProFTPD software has a weakness that lets attackers use special commands to access or change any files on the server remotely. This means someone could steal or alter your data without needing to log in.

2. What this means in plain English

If your organisation uses ProFTPD to manage files, this vulnerability could let hackers access sensitive information or damage your files. This risk is critical because it can happen from outside your network without any special access.

3. Could this affect a small business?

Small businesses or charities using ProFTPD for file transfers could be affected, especially if the server is accessible from the internet. If you do not use ProFTPD or do not have it exposed online, you are likely not at risk.

4. What to do now

  • Check if your organisation uses ProFTPD software for file transfers.
  • Ask your IT provider or software supplier if your ProFTPD installation is affected and if mitigations or updates are available.
  • If your ProFTPD server is internet-facing, ensure it is patched or apply vendor-recommended mitigations immediately.
  • If no fix is available, consider discontinuing use or restricting access to the ProFTPD server until it is secured.

5. Ask your IT provider

Can you confirm if our ProFTPD server is affected by the CVE-2015-3306 vulnerability, and what steps have been taken to mitigate or patch this critical security issue?

6. Bottom line

If you use ProFTPD, act quickly to secure your system against this actively exploited vulnerability.

Information based on CISA KEV, NVD and reputable security reporting.

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