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CVE.org (no NVD analysis yet)· CNA GitHub_M

CVE-2026-126345: basic-ftp: Uncaught TypeError in MLSD directory-listing parser via __proto__ fact name causes DoS in Client.list()

MediumCVSS 5.3 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 21/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: patrickjuchli basic-ftp 6.2.4.

Low priority for now. Upgrade to patrickjuchli basic-ftp 6.2.4 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org

basic-ftp is an FTP client for Node.js. Prior to 6.2.4, the MLSD directory-listing parser in src/parseListMLSD.ts uses untrusted fact names from the FTP server as keys in the plain-object factHandlersByName dictionary without checking that the resolved property is an own handler. A fact named __proto__ therefore resolves to Object.prototype, bypasses the missing-handler guard, and is called as though it were a function, producing a TypeError. The error propagates through Client.list() and APIs that depend on it because it is not an FTPError. A malicious or compromised FTP server, or an on-path attacker on a plaintext FTP session, can make the affected operation reject, and the Node.js process terminates under the default behavior in Node.js 15 and later only if the application leaves that rejection unhandled. This issue is fixed in version 6.2.4.

Published
Nov 12, 2026
Updated
Nov 12, 2026
EPSS
—

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · —

CNA vs NVD score

NVD
—
CNA · GitHub_M
5.3
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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  • Not in KEV: no record of exploitation in the wild
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When you'll hear from us

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  • when exploit code appears or is weaponized
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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • patrickjuchli basic-ftp

    • < 6.2.4affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
npmbasic-ftpbefore 6.2.46.2.4

Same product

patrickjuchli: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-27699Basic FTP has Path Traversal Vulnerability in its downloadToDir() method
    39Monitor
  • CVE-2026-39983FTP Command Injection via CRLF in basic-ftp
    35Monitor
  • CVE-2026-102990basic-ftp: Quadratic-time CPU denial of service in Client.list() Unix directory-listing parser (RE_LINE backtracking)
    32Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-41324Apr 24, 2026 · basic-ftp vulnerable to denial of service via unbounded memory consumption in Client.list()
    30Monitor
  • ← EarlierCVE-2026-44240May 12, 2026 · basic-ftp allows a malicious FTP server to cause client-side denial of service via unbounded multiline control response buffering
    30Monitor
  • Later →CVE-2026-126346Nov 12, 2026 · basic-ftp: Uncaught exception crashes the Node.js process when a password (or resumed-download path) contains CR/LF
    23Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
patrickjuchli basic-ftp6.2.4 · descriptionVendor (CNA)
npm:basic-ftp6.2.4Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. Fix recordedsame day
  3. TodayNov 13, 2026same day

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-1263460 days apartbasic-ftp: Uncaught exception crashes the Node.js process when a password (or resumed-download path) contains CR/LF
    23Monitor

Not on record for this CVE: EPSS history · researcher credit · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
low · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

Weakness class (CWE)

CWE-248 · Uncaught Exception

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records