CVE-2026-44240
Description
A flaw was found in basic-ftp, an FTP client for Node.js. A malicious or compromised FTP server can exploit this vulnerability by sending an unterminated multiline response during the initial FTP banner phase, before authentication. The client continuously appends attacker-controlled data and repeatedly reparses the accumulated buffer without enforcing a maximum size. This can lead to a client-side Denial of Service (DoS), causing the application to become unresponsive, consume excessive memory and CPU, and potentially result in process termination or service degradation.
Mitigation
To mitigate this issue, restrict applications using the `basic-ftp` client to connect only to trusted FTP servers. Implement firewall rules or network access controls to limit outbound connections from affected systems to known, legitimate FTP endpoints. This operational control reduces the exposure to malicious or compromised FTP servers that could exploit this vulnerability. A restart of the affected application may be required for changes to take effect.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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