Vulnerability in Proftpd
CVE-2026-35025
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (40.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 40.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Proftpd — versions 1.3.10
- Proftpd Project — versions 0
Weakness classification (CWE)
References
- github.com/proftpd/proftpd/issues/2170 (technical-description, Mitigation, Issue Tracking)
- www.proftpd.org/ (Product, product, Release Notes)
- www.vulncheck.com/advisories/proftpd-acl-bypass-via-proc-self-root-path-prefix-… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-35025?
- CVE-2026-35025 is a high-severity vulnerability in Proftpd, classified under Improper Link Resolution Before File Access. CVSS score: 8.1/10. Published 2026-06-24.
- How severe is CVE-2026-35025?
- High severity. CVSS v3 base score is 8.1 out of 10.