Knot Resolver before 5.5.3 allows remote attackers to cause a denial of service (CPU consumption) because of algorithmic complexity. During an attack, an authoritative server must return large NS sets or address sets.

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

  - Knot Resolver before 5.5.3 allows remote attackers to cause a denial of service (CPU consumption) because     of algorithmic complexity. During an attack, an authoritative server must return large NS sets or address     sets. (CVE-2022-40188)

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

The remote Ubuntu 16.04 ESM / 18.04 ESM / 20.04 LTS / 22.04 ESM host has packages installed that are affected by a vulnerability as referenced in the USN-6225-1 advisory.

    It was discovered that Knot Resolver did not correctly handle certain client options. A remote attacker     could send requests to malicous domains and cause a denial of service.

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

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

The remote Debian 10 host has packages installed that are affected by a vulnerability as referenced in the dla-3139 advisory.

    - -------------------------------------------------------------------------     Debian LTS Advisory DLA-3139-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/                           Chris Lamb     October 07, 2022                              https://wiki.debian.org/LTS
    - -------------------------------------------------------------------------

    Package        : knot-resolver     Version        : 3.2.1-3+deb10u1     CVE ID         : CVE-2022-40188

    It was discovered that there was a potential remote denial-of-service     vulnerability in the knot-resolver DNSSEC-validating DNS resolver.

    Remote attackers could have caused a denial of service via CPU     consumption by exploiting algorithmic complexity: during an attack,     an authoritative server would return large nameserver or address     sets.

    For Debian 10 buster, this problem has been fixed in version     3.2.1-3+deb10u1.

    We recommend that you upgrade your knot-resolver packages.

    For the detailed security status of knot-resolver please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/knot-resolver

    Further information about Debian LTS security advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://wiki.debian.org/LTS

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

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

ID	Name	Product	Family	Severity
224986	Linux Distros Unpatched Vulnerability : CVE-2022-40188	Nessus	Misc.	high
178222	Ubuntu 16.04 ESM / 18.04 ESM / 20.04 LTS / 22.04 ESM : Knot Resolver vulnerability (USN-6225-1)	Nessus	Ubuntu Local Security Checks	high
165789	Debian dla-3139 : knot-resolver - security update	Nessus	Debian Local Security Checks	high

Detections

Analytics

CVE-2022-40188

high

Tenable Plugins

high

high

high