CVE-2023-26249 - Vulnerability Details - OpenCVE

Description

Knot Resolver before 5.6.0 enables attackers to consume its resources, launching amplification attacks and potentially causing a denial of service. Specifically, a single client query may lead to a hundred TCP connection attempts if a DNS server closes connections without providing a response.

Published: 2023-02-21

Score: 7.5 High

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

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 vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2023-30073	Knot Resolver before 5.6.0 enables attackers to consume its resources, launching amplification attacks and potentially causing a denial of service. Specifically, a single client query may lead to a hundred TCP connection attempts if a DNS server closes connections without providing a response.

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

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00389.

Exploitation none

Automatable yes

Technical Impact partial

References

Link	Providers
https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html

History

Fri, 14 Mar 2025 19:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Subscriptions

Nic Knot Resolver

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2023-02-21T00:00:00.000Z

Updated: 2025-03-14T18:32:24.994Z

Reserved: 2023-02-21T00:00:00.000Z

Link: CVE-2023-26249

Vulnrichment

Updated: 2024-08-02T11:46:23.483Z

NVD

Status : Modified

Published: 2023-02-21T02:15:10.293

Modified: 2025-03-14T19:15:41.807

Link: CVE-2023-26249

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-770

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