CVE-2026-35025 ProFTPD ACL Bypass via /proc/self/root Path Prefix in RNFR

High 8.6 Published 24 Jun 2026 Updated 14 Jul 2026

Authenticated users can bypass ACL restrictions to rename and retrieve files from protected directories via path manipulation in RNFR.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-35025?

CVE-2026-35025 is a high-severity path traversal vulnerability in ProFTPD, published on 24 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

ProFTPD through 1.3.9b and 1.3.10rc2 contains an access control bypass vulnerability that allows authenticated FTP users to circumvent Directory ACL restrictions by prefixing paths with /proc/self/root in the RNFR command handler. Attackers can exploit the unresolved symlink components in dir_canonical_path() to cause dir_check() to perform lexical path comparisons that match no configured Directory block, enabling rename operations on files in DenyAll-protected directories and subsequent retrieval of those files. Mitigation: Sessions configured with DefaultRoot (chroot) are not affected, as chroot changes the directory to which /proc/self/root resolves.

Weakness: CWE-59

Which versions are affected by CVE-2026-35025?

It affects 1 product.

Products include Proftpd Proftpd.

How do I fix CVE-2026-35025?

No fix has been published for CVE-2026-35025 yet. Limit exposure of the affected software until one is available.

Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.

Is CVE-2026-35025 being exploited?

There is no known exploitation of CVE-2026-35025 in the wild and no public exploit code.

Sources

Also known as DEBIAN-CVE-2026-35025, GHSA-9vr4-2f43-pc8v, UBUNTU-CVE-2026-35025.