---
id: "CVE-2026-129121"
page: "https://infrastack.ai/live/CVE-2026-129121"
kind: "vulnerability"
aliases: ["CVE-2026-129121"]
title: "C-Kermit: malicious FTP server can overwrite files and run code"
severity: "medium"
cvss: 6.9
epss: null
exploited: false
status: "open"
category: "other"
products: []
ecosystems: []
tags: ["c-kermit", "ftp", "linux", "other", "unix"]
not_affected_if: ["no-ftp-client-use", "trusted-ftp-servers-only"]
published_at: "2026-11-13T17:17:29+00:00"
first_seen_at: "2026-11-13T17:48:00+00:00"
updated_at: "2026-11-13T17:48:59+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-129121", "first_seen_at": "2026-11-13T17:48:00+00:00"}]
exploit_sources: []
---

# C-Kermit: malicious FTP server can overwrite files and run code

Link for people: https://infrastack.ai/live/CVE-2026-129121 (this .md is for agents)

C-Kermit's recursive FTP get in doftpget() trusts file names from an FTP server's NLST or MLSD listing. A malicious server can return absolute paths, tilde names or dot-dot components so that files outside the download directory, such as .bashrc, are overwritten, which can lead to code execution.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version with `kermit` (look for the version banner) and compare it against the range `8.0.200` to before `11.1.515`.
- Look for scripts or jobs that run `MGET /RECURSIVE` against FTP servers you do not control.

## Fix

- C-Kermit: move to `11.1.515` or later

## Timeline

- 2026-11-13T17:48:00+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-129121

## Documents

- [advisory] Vendor advisory: github.com https://github.com/OpenKermit/ckermit/security/advisories/GHSA-vhrv-7jrq-95qj
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/c-kermit-8.0.200-before-11.1.515-path-traversal-via-ftp-mget-recursive
- [fix] Patch: github.com https://github.com/OpenKermit/ckermit/commit/9b1809b2ce2bcec08b7285deb1b7f0bcbef6a052
- [fix] Release notes: github.com https://github.com/OpenKermit/ckermit/releases/tag/v11.1.515

## From the sources

C-Kermit 8.0.200 before 11.1.515 contains a path traversal vulnerability in doftpget() in ckcftp.c that allows malicious FTP servers to write files outside the intended directory. Attackers can return absolute paths, tilde names, or dot-dot components in NLST or MLSD listings during MGET /RECURSIVE to overwrite files like .bashrc, leading to code execution.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_