CVE-2023-26249

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Published Feb 21, 2023 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

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.

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

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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.

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

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.708% probability within 30 days)

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

Mar 14, 2025 7:15 PM Scoring metrics updated View changes

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

Subscriptions

Nic Knot Resolver

Weaknesses

CWE-770

Sources

CVE record Updated: Mar 14, 2025, 6:32 PM

Status: PUBLISHED
Assigner: mitre
Published: Feb 21, 2023, 12:00 AM
Updated: Mar 14, 2025, 6:32 PM
Reserved: Feb 21, 2023, 12:00 AM

View source JSON

Vulnrichment Updated: Aug 2, 2024, 11:46 AM

Updated: Aug 2, 2024, 11:46 AM

NVD Updated: Jun 17, 2026, 5:42 AM

Status: Modified
Published: Feb 21, 2023, 2:15 AM
Modified: Jun 17, 2026, 5:42 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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