---
id: CVE-2026-102990
title: basic-ftp is an FTP client for Node.js
summary: >-
  basic-ftp is an FTP client for Node.js. Prior to 6.2.1, Client.list() can be
  forced by a malicious or compromised FTP server to spend quadratic CPU time
  parsing a directory listing because the RE_LINE expression in
  src/parseListUnix.ts b…
severity: high
cvss: 8.2
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cwe:
  - CWE-1333
vendor: patrickjuchli
product: basic-ftp
affected:
  - basic-ftp < 6.2.1
published: '2026-09-30'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T21:17:06.307'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102990'
references:
  - url: >-
      https://github.com/patrickjuchli/basic-ftp/commit/d0d9e07c56e519587bb50532ac6eadbb0cb0cfe9
    label: security-advisories@github.com
  - url: 'https://github.com/patrickjuchli/basic-ftp/releases/tag/v6.2.1'
    label: security-advisories@github.com
  - url: >-
      https://github.com/patrickjuchli/basic-ftp/security/advisories/GHSA-c475-qrg2-pj4r
    label: security-advisories@github.com
  - url: >-
      https://github.com/patrickjuchli/basic-ftp/security/advisories/GHSA-c475-qrg2-pj4r
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-30T20:05:43.038485Z'
cvssSource: cna
ingestedAt: '2026-09-30T20:23:19.513Z'
---

## Overview

basic-ftp is an FTP client for Node.js. Prior to 6.2.1, Client.list() can be forced by a malicious or compromised FTP server to spend quadratic CPU time parsing a directory listing because the RE_LINE expression in src/parseListUnix.ts backtracks across adjacent variable-length owner and group fields when a long Unix-style line has a valid prefix but cannot satisfy the later size and date fields. parseList() selects a parser from the last nonblank line and then applies it to every line, so a normal final line can select the Unix parser while an earlier crafted line blocks the Node.js event loop and freezes the process. This issue is fixed in version 6.2.1.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.