CVE-2020-12667 - Vulnerability Details - OpenCVE

Description

Knot Resolver before 5.1.1 allows traffic amplification via a crafted DNS answer from an attacker-controlled server, aka an "NXNSAttack" issue. This is triggered by random subdomains in the NSDNAME in NS records.

Published: 2020-05-19

Score: 7.5 High

EPSS: 2.6% Low

KEV: No

Impact:

Action:

Analysis

No analysis available yet.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:nic:knot_resolver:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
Debian DLA	DLA-3795-1	knot-resolver security update
Ubuntu USN	USN-7047-1	Knot Resolver vulnerabilities

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

The EPSS score is 0.02619.

Key SSVC decision points have not yet been added.

References

Link	Providers
http://cyber-security-group.cs.tau.ac.il/#
http://www.openwall.com/lists/oss-security/2020/05/19/2
https://en.blog.nic.cz/2020/05/19/nxnsattack-upgrade-resolvers-to-stop-new-kind-of-random-subdomain-attack/
https://lists.debian.org/debian-lts-announce/2024/04/msg00017.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/76Y4FITMOH6RVPWAANGV7NB2ZHPJJGDQ/
https://www.knot-resolver.cz/2020-05-19-knot-resolver-5.1.1.html

History

No history.

Subscriptions

Nic Knot Resolver

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2020-05-19T00:00:00.000Z

Updated: 2024-08-04T12:04:22.538Z

Reserved: 2020-05-05T00:00:00.000Z

Link: CVE-2020-12667

Vulnrichment

Updated: 2024-08-04T12:04:22.538Z

NVD

Status : Modified

Published: 2020-05-19T13:15:11.763

Modified: 2026-06-17T02:52:06.190

Link: CVE-2020-12667

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-400
Uncontrolled Resource Consumption

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