CVE-2023-26249

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html	Release Notes Vendor Advisory
https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html	Release Notes Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

21 Nov 2024, 07:50

Type	Values Removed	Values Added
References	~~() https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html - Release Notes, Vendor Advisory~~	() https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html - Release Notes, Vendor Advisory

02 Mar 2023, 23:20

Type	Values Removed	Values Added
CWE		CWE-770
CPE		cpe:2.3:a:nic:knot_resolver::::::::
References	~~(MISC) https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html -~~	(MISC) https://www.knot-resolver.cz/2023-01-26-knot-resolver-5.6.0.html - Release Notes, Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

21 Feb 2023, 14:50

Type	Values Removed	Values Added
New CVE

Information

Published : 2023-02-21 02:15

Updated : 2025-03-14 19:15

NVD link : CVE-2023-26249

Mitre link : CVE-2023-26249

CVE.ORG link : CVE-2023-26249

JSON object : View

Products Affected

nic

knot_resolver

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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7.5 /10