CVE-2021-40239

Name: CVE-2021-40239
Creator: NVD / NIST
Published: 2021-10-11T19:15:07.627+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.36%

Last modified Jun 17, 2026

CVE-2021-40239 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. A Buffer Overflow vulnerability exists in the latest version of Miniftpd in the do_retr function in ftpproto.c. EPSS estimates a 1.36% chance of exploitation in the next 30 days.

Description

A Buffer Overflow vulnerability exists in the latest version of Miniftpd in the do_retr function in ftpproto.c

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

1.36%

68.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Miniftpd Project	Miniftpd	1.0

References

https://github.com/Gabe-commiter/Miniftpd/issues/2Exploit, Third Party Advisory
https://github.com/Gabe-commiter/Miniftpd/issues/2Exploit, Third Party Advisory

Timeline

Published: Oct 11, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40239?

A Buffer Overflow vulnerability exists in the latest version of Miniftpd in the do_retr function in ftpproto.c

How severe is CVE-2021-40239?

CVE-2021-40239 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.36% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40239?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-40239?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST