PowerDNS Recursor up to 5.2.10/5.3.7/5.4.2 Zone ZoneToCache denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k1.23-

Summaryinfo

A vulnerability, which was classified as problematic, has been found in PowerDNS Recursor up to 5.2.10/5.3.7/5.4.2. Affected by this vulnerability is the function ZoneToCache of the component Zone Handler. Performing a manipulation results in denial of service. This vulnerability is reported as CVE-2026-42387. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in PowerDNS Recursor up to 5.2.10/5.3.7/5.4.2. It has been classified as problematic. This affects the function ZoneToCache of the component Zone Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is:

A malicious authoritative server can send a crafted zone via the ZoneToCache function that leads to a crash of the Recursor due to insuffcient input validation.

The weakness was disclosed by nurmukhammyed. The advisory is shared at docs.powerdns.com. This vulnerability is uniquely identified as CVE-2026-42387 since 04/27/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 5.2.11, 5.3.8 or 5.4.3 eliminates this vulnerability.

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

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.9
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Recursor 5.2.11/5.3.8/5.4.3

Timelineinfo

04/27/2026 CVE reserved
06/25/2026 +59 days Advisory disclosed
06/25/2026 +0 days VulDB entry created
06/25/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: docs.powerdns.com
Researcher: nurmukhammyed
Status: Confirmed

CVE: CVE-2026-42387 (🔒)
GCVE (CVE): GCVE-0-2026-42387
GCVE (VulDB): GCVE-100-373857

Entryinfo

Created: 06/25/2026 16:42
Changes: 06/25/2026 16:42 (66)
Complete: 🔍
Cache ID: 216::103

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