CVE-2026-33254

An attacker can create a large number of concurrent DoQ or DoH3 connections, causing unlimited memory allocation in DNSdist and leading to a denial of service. DOQ and DoH3 are disabled by default.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-04.html	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:powerdns:dnsdist::::::::
	cpe:2.3:a:powerdns:dnsdist::::::::

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Un atacante puede crear un gran número de conexiones DoQ o DoH3 concurrentes, causando una asignación de memoria ilimitada en DNSdist y provocando una denegación de servicio. DoQ y DoH3 están deshabilitados por defecto.

Information

Published : 2026-04-22 14:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-33254

Mitre link : CVE-2026-33254

CVE.ORG link : CVE-2026-33254

JSON object : View

Products Affected

powerdns

dnsdist

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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