CVE-2026-39983 | FTP Command Injection via CRLF in basic-ftp

Exp

basic-ftp is an FTP client for Node.js. Prior to 5.2.1, basic-ftp allows FTP command injection via CRLF sequences (\r\n) in file path parameters passed to high-level path APIs such as cd(), remove(), rename(), uploadFrom(), downloadTo(), list(), and removeDir(). The library's protectWhitespace() helper only handles leading spaces and returns other paths unchanged, while FtpContext.send() writes the resulting command string directly to the control socket with \r\n appended. This lets attacker-controlled path strings split one intended FTP command into multiple commands. This vulnerability is fixed in 5.2.1.

Published: 2026-04-09 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-39983 is rated High Exploit Risk (76.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.94%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-39983

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-39983

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 2.04% 1.94% -0.10%
2 2026-05-21 1.84% 2.04% +0.20%
3 2026-04-21 — 1.84% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-39983

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 3.9 4.7 [email protected]

Weakness enumeration for CVE-2026-39983

GitHub Security Advisory for CVE-2026-39983

GHSA-chqc-8p9q-pq6q · Severity: high · Ecosystem: npm — basic-ftp has FTP Command Injection via CRLF

OS Trackers for CVE-2026-39983

vendor priority summary link
debian not yet assigned CVE-2026-39983 not yet assigned priority: Debian including 1 source packages (node-proxy-agents), 3 status rows across 3 suites (forky, sid, trixie): resolved 2, open 1. https://security-tracker.debian.org/tracker/CVE-2026-39983
redhat high — https://access.redhat.com/security/cve/CVE-2026-39983
ubuntu medium CVE-2026-39983 medium priority: Ubuntu including 1 source packages (node-proxy-agents), 4 status rows across 4 suites (jammy, noble, questing, upstream): needs-triage 3, DNE 1. https://ubuntu.com/security/CVE-2026-39983

Affected software / configurations for CVE-2026-39983

Vendor Product Version Raw CPE
patrickjuchli basic-ftp < 5.2.1 cpe:2.3:a:patrickjuchli:basic-ftp:*:*:*:*:*:node.js:*:*

References for CVE-2026-39983

cvelogic Threat Intelligence