CVE-2021-40491

Name: CVE-2021-40491
Creator: NVD / NIST
Published: 2021-09-03T02:15:06.403+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.93%

Last modified Jun 17, 2026

CVE-2021-40491 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. The ftp client in GNU Inetutils before 2.2 does not validate addresses returned by PASV/LSPV responses to make sure they match the server address. This is similar to CVE-2020-8284 for curl.. EPSS estimates a 0.93% chance of exploitation in the next 30 days.

Description

The ftp client in GNU Inetutils before 2.2 does not validate addresses returned by PASV/LSPV responses to make sure they match the server address. This is similar to CVE-2020-8284 for curl.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

0.93%

56.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-345

Affected Software

Vendor	Product	Versions
Gnu	Inetutils	< 2.2
Debian	Debian Linux	10.0

References

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=993476Third Party Advisory
https://git.savannah.gnu.org/cgit/inetutils.git/commit/?id=58cb043b190fd04effdaea7c9403416b436e50ddPatch, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00033.htmlMailing List, Third Party Advisory
https://lists.gnu.org/archive/html/bug-inetutils/2021-06/msg00002.htmlMailing List, Vendor Advisory
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=993476Third Party Advisory
https://git.savannah.gnu.org/cgit/inetutils.git/commit/?id=58cb043b190fd04effdaea7c9403416b436e50ddPatch, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00033.htmlMailing List, Third Party Advisory
https://lists.gnu.org/archive/html/bug-inetutils/2021-06/msg00002.htmlMailing List, Vendor Advisory

Timeline

Published: Sep 3, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40491?

The ftp client in GNU Inetutils before 2.2 does not validate addresses returned by PASV/LSPV responses to make sure they match the server address. This is similar to CVE-2020-8284 for curl.

How severe is CVE-2021-40491?

CVE-2021-40491 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.93% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40491?

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-2021-40491?

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

Scan your code now

Source: NVD / NIST