CVE-2026-33594

A client can trigger excessive memory allocation by generating a lot of queries that are routed to an overloaded DoH backend, causing queries to accumulate into a buffer that will not be released until the end of the connection.

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 cliente puede desencadenar una asignación excesiva de memoria al generar muchas consultas que se enrutan a un backend DoH sobrecargado, lo que provoca que las consultas se acumulen en un búfer que no se liberará hasta el final de la conexión.

Information

Published : 2026-04-22 14:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-33594

Mitre link : CVE-2026-33594

CVE.ORG link : CVE-2026-33594

JSON object : View

Products Affected

powerdns

dnsdist

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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