CVE-2021-40797

Name: CVE-2021-40797
Creator: NVD / NIST
Published: 2021-09-08T20:15:11.06+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.70%

Last modified Jun 17, 2026

CVE-2021-40797 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. An issue was discovered in the routes middleware in OpenStack Neutron before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1. By making API requests involving nonexistent controllers, an authenticated user may cause the API worker to consume increasing amounts of memory, resulting in API performance degradation or denial of service.. EPSS estimates a 1.70% chance of exploitation in the next 30 days.

Description

An issue was discovered in the routes middleware in OpenStack Neutron before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1. By making API requests involving nonexistent controllers, an authenticated user may cause the API worker to consume increasing amounts of memory, resulting in API performance degradation or denial of service.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

1.70%

74.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-772

Affected Software

Vendor	Product	Versions
Openstack	Neutron	< 16.4.1
Openstack	Neutron	>= 17.0.0, < 17.2.1
Openstack	Neutron	>= 18.0.0, < 18.1.1

References

http://www.openwall.com/lists/oss-security/2021/09/09/2Mailing List, Patch, Third Party Advisory
https://launchpad.net/bugs/1942179Exploit, Issue Tracking, Third Party Advisory
https://security.openstack.org/ossa/OSSA-2021-006.htmlPatch, Vendor Advisory
http://www.openwall.com/lists/oss-security/2021/09/09/2Mailing List, Patch, Third Party Advisory
https://launchpad.net/bugs/1942179Exploit, Issue Tracking, Third Party Advisory
https://security.openstack.org/ossa/OSSA-2021-006.htmlPatch, Vendor Advisory

Timeline

Published: Sep 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40797?

How severe is CVE-2021-40797?

CVE-2021-40797 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.70% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40797?

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-2021-40797?

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

Scan your code now

Source: NVD / NIST