Low severity · published Jul 23, 2026
CVE-2026-52686
Wildcard CNAME proof validation bypass
3.7
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RE
Recursor · PowerDNS
5.2.0 before 5.2.12; 5.3.0 before 5.3.9; 5.4.0 before 5.4.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-52686
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-52686
docs.powerdns.com
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-10.html
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