PowerDNS Recursor up to 5.1.9/5.2.7/5.3.4 Zones allocation of resources

Summaryinfo

A vulnerability classified as problematic has been found in PowerDNS Recursor up to 5.1.9/5.2.7/5.3.4. This affects an unknown function of the component Zones Handler. This manipulation causes allocation of resources. This vulnerability is handled as CVE-2026-0398. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in PowerDNS Recursor up to 5.1.9/5.2.7/5.3.4 and classified as problematic. Affected by this vulnerability is some unknown processing of the component Zones Handler. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. As an impact it is known to affect availability. The summary by CVE is:

Crafted zones can lead to increased resource usage and crafted CNAME chains can lead to cache poisoning in Recursor.

The weakness was released by Yufan You. The advisory is shared at docs.powerdns.com. This vulnerability is known as CVE-2026-0398 since 11/28/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 298462 (Linux Distros Unpatched Vulnerability : CVE-2026-0398), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.1.10, 5.2.8 or 5.3.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (298462) and CERT Bund (WID-SEC-2026-0355). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Open Source PowerDNS

Productinfo

Type

• Domain Name Software

Vendor

• PowerDNS

Name

• Recursor

Version

• 5.1.0
• 5.1.1
• 5.1.2
• 5.1.3
• 5.1.4
• 5.1.5
• 5.1.6
• 5.1.7
• 5.1.8
• 5.1.9
• 5.2.0
• 5.2.1
• 5.2.2
• 5.2.3
• 5.2.4
• 5.2.5
• 5.2.6
• 5.2.7
• 5.3.0
• 5.3.1
• 5.3.2
• 5.3.3
• 5.3.4

License

• free

CPE 2.3info

• 🔒
• 🔒
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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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