Vulnerability · Published Jul 23, 2026 · Assigned by OX
CVE-2026-52686Wildcard CNAME proof validation bypass
Low 3.7
In plain English
A low-severity security flaw in Recursor from PowerDNS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)3.7Low
Exploit odds (30 days)0.2%top 94.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.24 | pdns-recursor | 5.4.4-r0 | ALPINE-CVE-2026-52686 |
| Debian:12 | pdns-recursor | no fix listed | DEBIAN-CVE-2026-52686 |
| Debian:13 | pdns-recursor | 5.2.12-0+deb13u1 | DEBIAN-CVE-2026-52686 |
| Debian:14 | pdns-recursor | 5.4.4-1 | DEBIAN-CVE-2026-52686 |
| Ubuntu:24.04:LTS | pdns-recursor | no fix listed | UBUNTU-CVE-2026-52686 |
| Ubuntu:26.04:LTS | pdns-recursor | no fix listed | UBUNTU-CVE-2026-52686 |
| Ubuntu:26.10 | pdns-recursor | no fix listed | UBUNTU-CVE-2026-52686 |
Affected products (as reported)
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N