CVE-2020-12667

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Published May 19, 2020 CVSS 3.1 · 7.5 High EPSS 2.6% KEV · Not listed

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.

Affected Products

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 solution or workaround provided in the CVE record

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

Metrics

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.

Exploit prediction score: 2.6% (2.612% probability within 30 days)

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

Weaknesses

CWE-400

Sources

CVE record Updated: Aug 4, 2024, 12:04 PM

Status: PUBLISHED
Assigner: mitre
Published: May 19, 2020, 12:00 AM
Updated: Aug 4, 2024, 12:04 PM
Reserved: May 5, 2020, 12:00 AM

View source JSON

Vulnrichment Updated: Aug 4, 2024, 12:04 PM

Updated: Aug 4, 2024, 12:04 PM

NVD Updated: Jun 17, 2026, 2:52 AM

Status: Modified
Published: May 19, 2020, 1:15 PM
Modified: Jun 17, 2026, 2:52 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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