CVE-2026-42390: Improper Input Validation in PowerDNS Recursor
An invalid zone might pass ZONEMD validation while it should not. This is only relevant if ZoneToCache is configured with ZONEMD validation.
AI Analysis
Technical Summary
This vulnerability in PowerDNS Recursor version 5.4.0 involves improper input validation related to ZONEMD (DNS zone message digest) validation. Specifically, an invalid zone might pass ZONEMD validation incorrectly if the ZoneToCache feature is configured to use ZONEMD validation. The issue is classified under CWE-20 (Improper Input Validation) and has a CVSS 3.1 base score of 5.3, indicating a medium severity. There is no indication of known exploits in the wild, and no official remediation or patch has been documented as of the publication date.
Potential Impact
The vulnerability allows an invalid DNS zone to pass ZONEMD validation improperly, potentially leading to integrity issues in DNS zone caching. There is no impact on confidentiality or availability according to the CVSS vector. This could affect DNS data integrity when ZONEMD validation is enabled in the ZoneToCache configuration.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or patch is documented, users should monitor PowerDNS advisories for updates. If possible, temporarily disabling ZONEMD validation in ZoneToCache configurations may reduce exposure until a fix is available.
CVE-2026-42390: Improper Input Validation in PowerDNS Recursor
Description
An invalid zone might pass ZONEMD validation while it should not. This is only relevant if ZoneToCache is configured with ZONEMD validation.
CVSS v3.1
Score 5.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in PowerDNS Recursor version 5.4.0 involves improper input validation related to ZONEMD (DNS zone message digest) validation. Specifically, an invalid zone might pass ZONEMD validation incorrectly if the ZoneToCache feature is configured to use ZONEMD validation. The issue is classified under CWE-20 (Improper Input Validation) and has a CVSS 3.1 base score of 5.3, indicating a medium severity. There is no indication of known exploits in the wild, and no official remediation or patch has been documented as of the publication date.
Potential Impact
The vulnerability allows an invalid DNS zone to pass ZONEMD validation improperly, potentially leading to integrity issues in DNS zone caching. There is no impact on confidentiality or availability according to the CVSS vector. This could affect DNS data integrity when ZONEMD validation is enabled in the ZoneToCache configuration.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or patch is documented, users should monitor PowerDNS advisories for updates. If possible, temporarily disabling ZONEMD validation in ZoneToCache configurations may reduce exposure until a fix is available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- OX
- Date Reserved
- 2026-04-27T08:53:58.839Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3d38354853345fc10a3538
Added to database: 06/25/2026, 14:16:21 UTC
Last enriched: 06/25/2026, 14:47:21 UTC
Last updated: 06/25/2026, 23:21:28 UTC
Views: 3
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