CVE-2026-52686 PUBLISHED

Wildcard CNAME proof validation bypass

Assigner: OX
Reserved: 08.06.2026 Published: 23.07.2026 Updated: 23.07.2026

The 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.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS Score: 3.7

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

CVSS 3.1

Product Status

Vendor	PowerDNS
Product	Recursor
Versions	Default: unaffected affected from 5.2.0 to 5.2.12 (excl.) affected from 5.3.0 to 5.3.9 (excl.) affected from 5.4.0 to 5.4.4 (excl.)

Credits

Qifan Zhang from Palo Alto Networks finder

References

https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-10.html

Problem Types

Insufficient Verification of Data Authenticity CWE