Wildcard CNAME proof validation bypass

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-52686
StatePUBLISHED
AssignerOX
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-07-23 09:16:26 UTC
Updated2026-07-23 15:48:25 UTC
DescriptionThe issue is a DNSSEC validation bypass where wildcard expansion proofs (NSEC/NSEC3 records) are accepted without signature validation when the wildcard answer is a CNAME or DNAME record.

Risk And Classification

Primary CVSS: v3.1 3.7 LOW from [email protected]

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS: 0.002550000 probability, percentile 0.170220000 (date 2026-07-23)

Problem Types: CWE-347 | Insufficient Verification of Data Authenticity | CWE-347 CWE-347 Improper Verification of Cryptographic Signature

VersionSourceTypeScoreSeverityVector
3.1[email protected]Secondary3.7LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
3.1CNACVSS3.7LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA PowerDNS Recursor affected 5.2.0 5.2.12 semver Not specified
CNA PowerDNS Recursor affected 5.3.0 5.3.9 semver Not specified
CNA PowerDNS Recursor affected 5.4.0 5.4.4 semver Not specified

References

ReferenceSourceLinkTags
docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-... [email protected] docs.powerdns.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Qifan Zhang from Palo Alto Networks (en)

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report