CVE-2026-119364: ProFTPD through 1.3.9e and 1.3.10rc4 mod_copy Symlink Following Write Bypass

Q: Who is exposed to this issue?

ProFTPD deployments that include mod_copy and allow authenticated FTP users to write into a directory where they can create symlinks are exposed if Limit WRITE restrictions protect other target locations. The affected versions are through 1.3.9e and 1.3.10rc1 through 1.3.10rc4.

Q: What does an attacker need to exploit it?

An attacker needs authenticated FTP access and permission to create a symlink in a writable directory. They can then invoke SITE COPY or SITE CPTO with that symlink as the destination to overwrite a file in a location where direct writes are denied.

Q: What can be done if updating is not immediately possible?

Prevent untrusted authenticated users from creating symlinks in writable FTP directories, and restrict or disable access to the SITE COPY and SITE CPTO functionality provided by mod_copy where possible. Review Limit WRITE-protected locations for files that could be overwritten through symlinked paths.

Published Oct 30, 2026

Updated

ProFTPD through 1.3.9e and 1.3.10rc1 through 1.3.10rc4 contains a link-following vulnerability in modcopy that allows authenticated FTP users to bypass Limit WRITE restrictions via symlinks. Attackers can place a symlink in a writable directory and use SITE COPY or SITE CPTO to overwrite files in write-denied locations.

Affected Software

4 affected components

debian/proftpd-dfsg*

debian/proftpd-dfsg<=1.3.8+dfsg-4+deb12u5, <=1.3.8+dfsg-4+deb12u4, <=1.3.8.c+dfsg-4+deb13u3, <=1.3.9d~dfsg-1, <=1.3.9e~dfsg-2

Event History

Oct 30, 2026

CVE Published

via MITRE·11:30 AM

Data Sourced

via MITRE·11:30 AM

DescriptionSeverityWeakness

Data Sourced

via NVD·12:16 PM

DescriptionSeverityWeakness

Data Sourced

via OSV·12:16 PM

Affected Software

Frequently Asked Questions

Who is exposed to this issue?

ProFTPD deployments that include mod_copy and allow authenticated FTP users to write into a directory where they can create symlinks are exposed if Limit WRITE restrictions protect other target locations. The affected versions are through 1.3.9e and 1.3.10rc1 through 1.3.10rc4.

What does an attacker need to exploit it?

An attacker needs authenticated FTP access and permission to create a symlink in a writable directory. They can then invoke SITE COPY or SITE CPTO with that symlink as the destination to overwrite a file in a location where direct writes are denied.

What can be done if updating is not immediately possible?

Prevent untrusted authenticated users from creating symlinks in writable FTP directories, and restrict or disable access to the SITE COPY and SITE CPTO functionality provided by mod_copy where possible. Review Limit WRITE-protected locations for files that could be overwritten through symlinked paths.

CVE-2026-119364: ProFTPD through 1.3.9e and 1.3.10rc4 mod_copy Symlink Following Write Bypass

Affected Software

Event History

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

What can be done if updating is not immediately possible?

Company

Resources

Contact

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

What can be done if updating is not immediately possible?