8.2
HIGH CVSS 4.0
CVE-2026-102990
basic-ftp: Quadratic-time CPU denial of service in Client.list() Unix directory-listing parser (RE_LINE backtracking)
Description

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.

INFO

Published Date :

Sept. 30, 2026, 8:17 p.m.

Last Modified :

Sept. 30, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-102990 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Patrickjuchli basic-ftp
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 4.0 HIGH [email protected]
Solution
Update basic-ftp to version 6.2.1 or later to fix a CPU-intensive parsing vulnerability.
  • Update basic-ftp to version 6.2.1 or later.
  • Review server parsing logic for efficiency.
  • Ensure only trusted servers are connected.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-102990 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-102990 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-102990 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-102990 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 30, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/patrickjuchli/basic-ftp/security/advisories/GHSA-c475-qrg2-pj4r
    Added SSVC {'id': 'CVE-2026-102990', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-30T20:05:43.038485Z'}
  • New CVE Received by [email protected]

    Sep. 30, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-1333
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/102xxx/CVE-2026-102990.json">CVE-2026-102990</a>
    Added Reference https://github.com/patrickjuchli/basic-ftp/commit/d0d9e07c56e519587bb50532ac6eadbb0cb0cfe9
    Added Reference https://github.com/patrickjuchli/basic-ftp/releases/tag/v6.2.1
    Added Reference https://github.com/patrickjuchli/basic-ftp/security/advisories/GHSA-c475-qrg2-pj4r
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.