A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the IPv6 addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations. Only deployments using the Open vSwitch driver are affected. Source: OpenStack project. Versions before openstack-neutron 15.3.3, openstack-neutron 16.3.1 and openstack-neutron 17.1.1 are affected.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted     packets, anyone in control of a server instance connected to the virtual switch can impersonate the IPv6     addresses of other systems on the network, resulting in denial of service or in some cases possibly     interception of traffic intended for other destinations. Only deployments using the Open vSwitch driver     are affected. Source: OpenStack project. Versions before openstack-neutron 15.3.3, openstack-neutron     16.3.1 and openstack-neutron 17.1.1 are affected. (CVE-2021-20267)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - A flaw was found in openstack-neutron's default Open vSwitch firewall rules. By sending carefully crafted
    packets, anyone in control of a server instance connected to the virtual switch can impersonate the IPv6
    addresses of other systems on the network, resulting in denial of service or in some cases possibly
    interception of traffic intended for other destinations. Only deployments using the Open vSwitch driver
    are affected. Source: OpenStack project. Versions before openstack-neutron 15.3.3, openstack-neutron
    16.3.1 and openstack-neutron 17.1.1 are affected. (CVE-2021-20267)

The remote Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-6067-1 advisory.

    David Sinquin discovered that OpenStack Neutron incorrectly handled the default Open vSwitch firewall     rules. An attacker could possibly use this issue to impersonate the IPv6 addresses of other systems on the     network. This issue only affected Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-20267)

    Jake Yip and Justin Mammarella discovered that OpenStack Neutron incorrectly handled the linuxbridge     driver when ebtables-nft is being used. An attacker could possibly use this issue to impersonate the     hardware addresss of other systems on the network. This issue only affected Ubuntu 18.04 LTS, and Ubuntu     20.04 LTS. (CVE-2021-38598)

    Pavel Toporkov discovered that OpenStack Neutron incorrectly handled extra_dhcp_opts values. An attacker     could possibly use this issue to reconfigure dnsmasq. This issue only affected Ubuntu 18.04 LTS, and     Ubuntu 20.04 LTS. (CVE-2021-40085)

    Slawek Kaplonski discovered that OpenStack Neutron incorrectly handled the routes middleware. An attacker     could possibly use this issue to cause the API worker to consume memory, leading to a denial of service.
    This issue only affected Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-40797)

    It was discovered that OpenStack Neutron incorrectly handled certain queries. A remote authenticated user     could possibly use this issue to cause resource consumption, leading to a denial of service.
    (CVE-2022-3277)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 10 / 11 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-4983 advisory.

    Pavel Toporkov discovered a vulnerability in Neutron, the OpenStack virtual network service, which allowed     a reconfiguration of dnsmasq via crafted dhcp_extra_opts parameters. For the oldstable distribution     (buster), this problem has been fixed in version 2:13.0.7+git.2021.09.27.bace3d1890-0+deb10u1. This update     also fixes CVE-2021-20267. For the stable distribution (bullseye), this problem has been fixed in version     2:17.2.1-0+deb11u1. This update also fixes CVE-2021-38598. We recommend that you upgrade your neutron     packages. For the detailed security status of neutron please refer to its security tracker page at:
    https://security-tracker.debian.org/tracker/neutron

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
255408	Linux Distros Unpatched Vulnerability : CVE-2021-20267	Nessus	Misc.	Local	high
433415	SCA: security update for neutron (GHSA-w8hx-f868-pvch)	Tenable Cloud Security	SCA Checks	Local	high
433415	SCA: security update for neutron (GHSA-w8hx-f868-pvch)	Tenable Self-Hosted Container Security	SCA Checks	Local	high
175565	Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS : OpenStack Neutron vulnerabilities (USN-6067-1)	Nessus	Ubuntu Local Security Checks	Local	high
153993	Debian DSA-4983-1 : neutron - security update	Nessus	Debian Local Security Checks	Local	critical

Detections

Analytics

CVE-2021-20267

high

Tenable Plugins

high

high

high

high

critical