CVE-2026-33601
Received Received - Intake
Null Pointer Dereference in zoneToCache Causes DoS in DNS Server

Publication date: 2026-04-22

Last updated on: 2026-04-27

Assigner: Open-Xchange

Description
If you use the zoneToCache function with a malicious authoritative server, an attacker can send a zone that result in a null pointer dereference, caused by a missing consistency check and leading to a denial of service.
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Meta Information
Published
2026-04-22
Last Modified
2026-04-27
Generated
2026-06-16
AI Q&A
2026-04-23
EPSS Evaluated
2026-06-15
NVD
CVE-2026-33601
EUVD
EUVD-2026-24733
Affected Vendors & Products
Showing 3 associated CPEs
Vendor Product Version / Range
powerdns recursor From 5.2.0 (inc) to 5.2.9 (exc)
powerdns recursor From 5.3.0 (inc) to 5.3.6 (exc)
powerdns recursor 5.4.0
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-476 The product dereferences a pointer that it expects to be valid but is NULL.
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Executive Summary

This vulnerability occurs when the zoneToCache function interacts with a malicious authoritative server. The attacker can send a specially crafted zone that causes a null pointer dereference due to a missing consistency check in the function.

This flaw leads to a denial of service condition, meaning the affected system or application can crash or become unavailable.

Impact Analysis

The primary impact of this vulnerability is a denial of service (DoS). An attacker exploiting this issue can cause the affected system to crash or become unresponsive, disrupting normal operations.

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